Add device part of DTrace/MIPS code
Make lockstat and profile modules x86-only
Jusy use i386 version of cyclic_machdep.c on all supported architectures.
It's generic enough to cover all of them.
Add DTrace-related part to machine-dependent code:

- DTrace trap handler
- invop-related variables (unused on MIPS but still referenced from dtrace)
Build libproc and librtld_db for MIPS
Add stub file for pid probe. It's required although pid probe is not supported
on MIPS yet
Enable build of DTrace-related userland parts for MIPS
Build CTF tools as a part of toolchain for cross-compilation case
Remap PMC interrupt for all cores
Document the show alias and add an EXAMPLES section.
Fix the following clang warning in sys/dev/dcons/dcons.c, caused by the
recent changes in sys/x86/include/endian.h:

  sys/dev/dcons/dcons.c:190:15: error: implicit conversion from '__uint32_t' (aka 'unsigned int') to '__uint16_t' (aka 'unsigned short') changes value from 1684238190 to 28526 [-Werror,-Wconstant-conversion]
	  buf->magic = ntohl(DCONS_MAGIC);
		       ^~~~~~~~~~~~~~~~~~
  sys/sys/param.h:306:18: note: expanded from:
  #define ntohl(x)        __ntohl(x)
			  ^
  ./x86/endian.h:128:20: note: expanded from:
  #define __ntohl(x)      __bswap32(x)
			  ^
  ./x86/endian.h:78:20: note: expanded from:
	      __bswap32_gen((__uint32_t)(x)) : __bswap32_var(x))
			    ^
  ./x86/endian.h:68:26: note: expanded from:
	  (((__uint32_t)__bswap16(x) << 16) | __bswap16((x) >> 16))
				  ^
  ./x86/endian.h:75:53: note: expanded from:
	      __bswap16_gen((__uint16_t)(x)) : __bswap16_var(x)))
					       ~~~~~~~~~~~~~ ^

This is because the __bswapXX_gen() macros (for x86) call the regular
__bswapXX() macros.  Since the __bswapXX_gen() variants are only called
when their arguments are constant, there is no need to do that constancy
check recursively.  Also, it causes the above error with clang.

Fix it by calling __bswap16_gen() from __bswap32_gen(), and similarly,
__bswap32_gen() from  __bswap64_gen().

While here, add extra parentheses around the __bswap16_gen() macro
expansion, to prevent unexpected side effects.
Given that this is a host-PCI-Express bridge driver, create the parent
DMA tag with a 4 GB boundary as required by PCI-Express. With r232403 in
place this actually is redundant. However, the host-PCI-Express bridge
driver is the more appropriate place for implementing this restriction.

MFC after:	3 days
Remove superfluous paragraph macro.
Initialize the mutexes used for the NVM and the swflag as MTX_DUPOK in
order to avoid otherwise harmless witness warnings when these are acquired
at the same time and due to both using MTX_NETWORK_LOCK as their type.
The right fix actually would be to use different, descriptive types for
these. However, the latter would require undesirable changes to the shared
code base. Another approach would be to just supply NULL as the type, which
was deemed as less desirable though as it would cause the unique but cryptic
name also to be used for the type and to diverge from the type used by other
network device drivers.

MFC after:	1 week
Minor mdoc fixes.
Consistently update to the MPI header set version 01.05.20 after r224761.
Requested by:	mjacob

MFC after:	1 week
Add QGE-X to the list of known-working cards.

MFC after:	1 week
Add cas(4), gem(4) and hme(4) to x86 GENERICs as suggested by netchild@ in
<20120222095239.Horde.0hpYHJjmRSRPRKzXsoFRbYk@webmail.leidinger.net>.
According to some private emails received, it apparently is not unpopular
to use at least Quad GigaSwift cards driven by cas(4) in x86 machines.

MFC after:	1 week
Direct users to csup instead of cvsup in the csup-file boilerplate text.

Reviewed by:	maxim, des, swills
Approved by:	cperciva
MFC after:	3 days
- Make the default values for tcsh more user friendly
- Add an examples file with many of the not accepted suggestions from the discussion

PR:		conf/160689
Reviewed by:	many
Discussed on:	current
Approved by:	cperciva