Tidy up MakefileProto.FBSD.in

We don't support FreeBSD 6.x and older now.  As such, we can convert
entirely to the "new" world order, and not have to worry about adding
new sysnames to the conditionals every time we add them.

(The sense of the conditionals should really have been reversed anyway,
so that the default case would catch new sysnames correctly.  Too late now.)

Change-Id: Iad5d8b6edb9140b38568ab57ffecf0cfdaf1cbd3
FreeBSD: VOP_MMAP has been dead since 1996

Clang complains that our (K&R!) declaration of struct vop_mmap_args
will only be visible within the (empty) function.
With the kernel's CFLAGS, though, this is fatal.
Remove the dead code.

Reviewed-on: http://gerrit.openafs.org/9856
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Derrick Brashear <shadow@your-file-system.com>
(cherry picked from commit a63e6747abd33fef40da16312dfc22d052bffd00)

Change-Id: I538e8ba387a3fd90bcb89ea8faac7ad6973aa7f3
FBSD: Remove include directive for nonexistent file

In the bsd.kmod.mk world, this becomes a fatal error.

Reviewed-on: http://gerrit.openafs.org/5033
Reviewed-by: Derrick Brashear <shadow@dementia.org>
Tested-by: Derrick Brashear <shadow@dementia.org>
(cherry picked from commit 037f3251cd8fa318ad8320a061368efedc480c37)

Change-Id: Ief03a620ed4ce2cf84dd90a84df4a2ab1247fd9a
Catch up to FreeBSD VM object read/write locks

Upstream r248084 changed the vm_object mutex to be a rwlock,
allowing for future optimizations.  This is a KPI change, so
introduce conditionals to be compatible with both versions of the KPI.

Change-Id: I6e3101bc80262480035dee4c5b2d1b9cbc44b57b
Reviewed-on: http://gerrit.openafs.org/10295
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Derrick Brashear <shadow@your-file-system.com>
Fix build for FreeBSD 10.0

Move a rmlock.h inclusion up a bit so that the vm headers can get the
rmlock assertion (and other) macros they need.

The filedesc structure has been expanded on FreeBSD to support a
stronger capabilities system; getting to the actual file descriptor
requires another structure access.

limits.h and stdarg.h need sys/ and machine/ prefixes for inclusion in the
kernel on FreeBSD.  Unlike on master, we did not have extra -I arguments
to remove.

Catch up to VM layer changes.

This builds, but crashes at runtime due to some ABI incompatibilities
that appear in the rx event layer; those will be fixed in a separate patch.

Change-Id: Icc253b1e938a58a7ab8d1b789c82b9b940d263fd