Flatten sysdeps/unix/bsd/bsd4.4 into sysdeps/unix/bsd.

As discussed in
<https://sourceware.org/ml/libc-alpha/2012-04/msg00840.html> and
<https://sourceware.org/ml/libc-alpha/2012-04/msg00989.html>, it seems
appropriate to flatten sysdeps/unix/bsd/bsd4.4 into sysdeps/unix/bsd.

The bulk of the patch is just moving files.  The only other changes
are: update paths in sysdeps/mach/hurd/Implies and
sysdeps/unix/sysv/linux/wait3.c; merge the two syscalls.list files,
with the removal of syscalls that were in
sysdeps/unix/bsd/syscalls.list but overridden in the bsd4.4 directory
by .c files there.

Tested x86_64.  The installed shared libraries are identical before
and after the patch except for libc.so where the move of wait3.c
(included by sysdeps/unix/sysv/linux/wait3.c) affects debug info, but
the disassembly is unchanged.

	* sysdeps/mach/hurd/Implies: Change unix/bsd/bsd4.4 to unix/bsd.
	* sysdeps/unix/bsd/syscalls.list (chflags): Add entry from
	sysdeps/unix/bsd/bsd4.4/syscalls.list.
	(fchflags): Likewise.
	(revoke): Likewise.
	(setlogin): Likewise.
	(sigaltstack): Likewise.
	(wait4): Likewise.
	(sigblock): Remove.
	(sigsetmask): Likewise.
	(wait3): Likewise.
	(waitpid): Likewise.
	* sysdeps/unix/bsd/bsd4.4/syscalls.list: Remove file.
	* sysdeps/unix/sysv/linux/wait3.c: Update directory of included
	file.
	* sysdeps/unix/bsd/bsd4.4/Makefile: Move to ...
	* sysdeps/unix/bsd/Makefile: ... here.
	* sysdeps/unix/bsd/bsd4.4/Versions: Move to ...
	* sysdeps/unix/bsd/Versions: ... here.
	* sysdeps/unix/bsd/bsd4.4/bits/sockaddr.h: Move to ...
	* sysdeps/unix/bsd/bits/sockaddr.h: ... here.
	* sysdeps/unix/bsd/bsd4.4/cmsg_nxthdr.c: Move to ...
	* sysdeps/unix/bsd/cmsg_nxthdr.c: ... here.
	* sysdeps/unix/bsd/bsd4.4/sigblock.c: Move to ...
	* sysdeps/unix/bsd/sigblock.c: ... here.
	* sysdeps/unix/bsd/bsd4.4/sigsetmask.c: Move to ...
	* sysdeps/unix/bsd/sigsetmask.c: ... here.
	* sysdeps/unix/bsd/bsd4.4/sigvec.c: Move to ...
	* sysdeps/unix/bsd/sigvec.c: ... here.
	* sysdeps/unix/bsd/bsd4.4/tcdrain.c: Move to ...
	* sysdeps/unix/bsd/tcdrain.c: ... here.
	* sysdeps/unix/bsd/bsd4.4/tcgetattr.c: Move to ...
	* sysdeps/unix/bsd/tcgetattr.c: ... here.
	* sysdeps/unix/bsd/bsd4.4/tcsetattr.c: Move to ...
	* sysdeps/unix/bsd/tcsetattr.c: ... here.
	* sysdeps/unix/bsd/bsd4.4/wait.c: Move to ...
	* sysdeps/unix/bsd/wait.c: ... here.
	* sysdeps/unix/bsd/bsd4.4/wait3.c: Move to ...
	* sysdeps/unix/bsd/wait3.c: ... here.
	* sysdeps/unix/bsd/bsd4.4/waitpid.c: Move to ...
	* sysdeps/unix/bsd/waitpid.c: ... here.
Fix ldbl-128 lgammal for small negative arguments (bug 16337).

This patch fixes bug 16337, ldbl-128 lgammal spurious overflows for
small negative arguments (the arguments in question are already in the
testsuite).  The implementation uses the reflection formula to compute
lgamma of negative x from lgamma of -x, effectively resulting in a
calculation -log(x^2) + log(-x); cancellation isn't problematic in
this case (bugs for problematic cancellation in lgamma are 2542, 2543,
2558), but the x^2 calculation can underflow (in which case there is
spurious logic to return an overflowing value - lgamma can only ever
correctly overflow for large positive arguments, though tgamma can
overflow for small arguments of either sign as well as large positive
arguments).  The fix is simply to calculate the result directly with
logl when the argument is a small enough negative number.

Tested mips64.

	* sysdeps/ieee754/ldbl-128/e_lgammal_r.c (__ieee754_lgammal_r):
	Calculate results for small negative arguments directly rather
	than using reflection formula with special underflow handling.