Style.

Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
sh: Add new tests to the Makefile.
Invalidate the cache for the named posix semaphore when opened and
actual file storing the semaphore object is different from the file
created on the first open.  Store the file st_dev and st_ino members
of the struct stat in the semaphore structure on open, and compare
them with the attributes of the opened file to detect unlink and
re-creation.

This fixes an issue of sem_unlink(3) failing to flush the named entry
in the semaphore list for the current or remote process, making
sem_unlink(3) not correctly operating if the unlinked semaphore is
still opened.

Reported by:	Joris Giovannangeli <joris@giovannangeli.fr>
PR:	standards/189353
Reviewed by:	jilles (previous version)
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
sh: In getopts, unset OPTARG where POSIX says we should.
About 9% of the pmap_protect() calls being performed by vm_map_copy_entry()
are unnecessary.  Eliminate the unnecessary calls.

Reviewed by:	kib
MFC after:	1 week
Sponsored by:	EMC / Isilon Storage Division
When mapping device memory, use PTE_DEVICE rather than PTE_NOCACHE.
On armv4 these are defined as synonyms right now, but it's a bit ambiguous
what NOCACHE means (is buffering/write-combining also enabled or not?); this
is a first step towards replacing PTE_NOCACHE with a less ambiguous name.
Rename platform_gpio_init to be SoC specific, and make it static as it's
only called from this file.
Rename platform_gpio_init to be platform specific, and make it static as
it's only used from this file.
Really, I don't want to install src.opts.mk at all.
Rename platform_gpio_init to be SoC specific