Log Message:
The previous commit message was botched; this commit message applies
to graphics/MesaLib as well.

I've added some distribution patches for bug fixes (yes, already, it's
true) and proper DragonFly support (see the sysctl-related changes
in MesaLib/Makefile).  Agressively tracking these patches is the only
way to ensure we squash as many bugs as possible.  No patches in a
given release branch (in this case Mesa_7_0_branch) should ever
merit a bump to BUILDLINK_ABI_DEPENDS.

The head GIT commit ref for patch 002 is:
27b6fa56156673d6e7e6839658bae10de161588b

In the future, I'm going to write some sort of script or something
to manage this, but this will suffice for now.  I may also break
out some of the patch logic into a seperate mk file so that it can
be included by the xorg server, thereby ensuring the sources
are synchronized.

In other news:  I have patches for libdrm to use NetBSD's atomic
ops.  They aren't used in the library proper.  Rather, the
DRM_CAS macro in xf86drm.h now uses atomic_cas_uint.  This is, I believe,
important for proper operation, as this macro is used for context/device
locks in userland.  When I commit the update to libdrm, I will simultaneously
commit a new drm_atomic.h in the kernel.  The atomic ops there now
really do not merit the designation 'atomic'.