Copy stable/11@r303970 to releng/11.0 as part of the 11.0-RELEASE
cycle.

Prune svn:mergeinfo from the new branch, and rename it to RC1.

Update __FreeBSD_version.

Use the quarterly branch for the default FreeBSD.conf pkg(8) repo and
the dvd1.iso packages population.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Copy head@r302406 to stable/11 as part of the 11.0-RELEASE cycle.
Prune svn:mergeinfo from the new branch, as nothing has been merged
here.

Additional commits post-branch will follow.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Re-support CWARNFLAGS, lost when bsd.sys.mk was removed. Also, support
CWARNFALGS.$file centrally so we don't have to have it in all the
places. Remove a few warning flags that are no longer needed.
Also, always use -Wno-unknown-pragma to (hopefully temporarily) work
around #pragma ident in debug.h in the opensolaris code. Remove some
stale warning suppression that's no longer necessary.

Remove aicasm as a build dependency. It made sense when the ahc and ahd
drivers and their firmware were under active development, but those days
have passed. The firmware now exists in pre-compiled form, no longer
dependent on it's sources or on aicasm. If you wish to rebuild the
firmware from source, the glue still exists under the 'make firmware'
target in sys/modules/aic7xxx.

This also fixes the problem introduced with r257777 et al with building
kernels the old fashioned way in sys/$arch/compile/$CONFIG when the
ahc/ahd drivers were included.

Disable -Wconstant-conversion warnings for the aic7xxx module in a more
fine-grained way: only add the option for the specific .c files that
need them, like via sys/conf/files.

MFC after: 1 week

Amend r228779 by also disabling -Wconstant-conversion warnings for the
aic7xxx module.

MFC after: 1 week

Allow the ahc and ahd drivers to be built as modules. This also
breaks the ahc driver into a core back-end and pci and eisa
front-ends.