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

amdsbwd: new driver for AMD SB600/SB7xx watchdog timer

The hardware is compliant with WDRT specification, so I originally
considered including generic WDRT watchdog support, but decided
against it, because I couldn't find anyone to the code for me.
WDRT seems to be not very popular.
Besides, generic WDRT porbably requires a slightly different driver
approach.

Reviewed by: des, gavin, rpaulo
MFC after: 3 weeks