Support for dynamic PAGE_SIZE

This patch adds support for dynamic PAGE_SIZE values. It
is a little bit invasive in several aspects:

* it modifies the startup code. We need to know the position of
  the elf-info auxilary table which is located after 'environ'.
  We can not use 'environ' directly because it might be modified
  by the application.

  Hence, an additional __elfinfo variable is placed into .bss and
  filled in the startup code. Depending on platform, this adds
  4-8 instructions and an additional pointer to .bss.

  I tested only the i386 and x86_64 modifications; it would be
  nice when people with corresponding hardware would test the
  other ones. I am especially uncertain regarding the parisc
  changes.

  The elf-info stuff (which might be interesting e.g. for dynamic
  linking or sysconf(_SC_CLK_TCK)) can be enabled without the
  dynamic pagesize too.

* it removes the 'PAGE_SIZE' macro from <sys/shm.h>; this will
  break compilation of existing userspace application which are
  using this deprecated macro

* I added a new internal 'dietpagesize.h' header which defines

  | __DIET_PAGE_SIZE
  | __DIET_PAGE_SHIFT

  macros. These return either builtin constants (when
  WANT_DYN_PAGESIZE is not selected), or values derived from
  __libc_getpagesize().

  Every usage of PAGE_SIZE in dietlibc code was replaced by these
  macros.

* due to the previous point, the internal 'struct __dirstream'
  was modified. I replaced

  | getdents64(d->fd,(struct dirent64*)d->buf, sizeof (d->buf)-1);

  with

  | getdents64(d->fd,(struct dirent64*)d->buf,  __DIRSTREAM_BUF_SIZE-1);

  literally but I am not sure where the '-1' is coming from.
  There is one hunk, where this '-1' is missing so I think the
  '-1' should be removed from all calls to getdents64().

* changes affect the *alloc() functions too; on x86_64 around 64
  bytes were added to .text of alloc.o

* the new testprogramm requires a 'getconf' binary which returns
  the correct values for PAGE_SIZE and CLK_TCK

Patch seems to work fine on i386, x86_64, ppc and ppc64.  Things
went a little bit complicated with linux 2.6.25; previous kernels
exported a elf_addr_t type in <linux/elf.h> which is used in the
auxilary elf-info table. Now, this is not available anymore and I
use a type derived from __WORD_SIZE.
Fixes/enhancements for INF/NAN handling in printf()

This patch adds support for uppercase 'F' and 'G' printf format
specifiers.  It fixes handling of -INF values in __dtostr() too;
previously, there was

| unsigned int i;
| if ((i=isinf(d))) return copystring(buf,maxlen,i>0?"inf":"-inf");
                                                 ~~~
which evaluated to true everytime. The copystring() function
worked for 3-letter words only but not for '-inf'.

The last argument of __dtostr() was changed from a boolean flag to
a bitmask. Bit 0 encodes 'g' or 'f', and bit 1 lower-/uppercase.
There should be probably added some macros for them; for now,
these values are used directly.

Please note that this might affect other applications (liblowfat?)
too which are using __dtostr().

'isinf(3)' is a builtin with gcc 4.3 and does not give a hint
about the signess of the infinity anymore. Hence, this patch uses
a more portable way where needed.
Fixes/enhancements in str?time() functions

This patch changes the used format for %x and %X specifiers in
strptime(3) to match these specified by SUSv2.  It adds support
for '%F' in strftime(3) too.
Fixes for -Werror-no-implicit-functions

Some fixes for issues preventing builds with
'-Werror-implicit-function-declaration'.
__noreturn__ annotation for abort(3)

SUSv2 says about abort(3):

  The abort() function shall not return.

Hence, an '__attribute__((__noreturn__))' should be added to the
abort(3) declaration.
Several testsuite fixes/enhancments

* test/getmntent.c: I removed the checks which called endmntent()
  multiple times resp. with a NULL pointer.  Behavior in first
  case is undefined and latter causes a segfault (I could not
  find documentation that this is allowed).  Hence, it does not
  make sense to test this.

* test/stdlib/tst-malloc.c: test 'malloc(0)' only, when
  WANT_MALLOC_ZERO is set

* test/time/tst-strftime.c: the '%Zu' printf format specifier is
  bogus (from libc5 ages). I replaced it with the '%zu' one.

  Please note, that this test still fails because it uses glibc
  specific features.

* test/time/tst-strptime.c: removed tests which set a non-C
  locale. Broken usage of 'strptime()' result was fixed too.
  This test should succeed now.

* test/math.c: this test was added while working on the '%F/%G'
  patch and verifies the isinf() + isnan() functions.

* fixes lot of broken printf() format specifiers

* fixes tests using isinf(); the math.c test checks the dietlibc
  implementation of isinf() (which differs between positive and
  negative inf). All other tests use boolean retval only and test
  for the signess of the values
minor cleanups in stackgap.c
LOCAL: cvsimport make target
test/mmap_test: specify file permissions on O_CREAT
test/pipe: close fd 3+4
test/adjtime: made test more useful...
test/if_nameindex: let test fail when if_nameindex(3) failed
utime: optimize C wrapper and added missing headers

Include headers only, when required.  Include <sys/time.h> too and
define _BSD_SOURCE.

Signed-off-by: Enrico Scholz <enrico.scholz@informatik.tu-chemnitz.de>
rpc: fixed some alignment issues
added ftruncate testcase
ceil(3): imported patch with ceil(3) from OpenEmbedded
mkstemp: open file with O_LARGEFILE

File descriptor is returned to application which might apply 64 bit
operations on it. These operations will fail when O_LARGEFILE was not
set.

Signed-off-by: Enrico Scholz <enrico.scholz@informatik.tu-chemnitz.de>
remove __fflush_stdin

According to the fflush(3) man-page, only output buffers are flushed.
Anything else wouldn't make much sense anyway.
add add select syscall for powerpc{,64}
add ipc syscalls for parisc