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

A number of places in the source tree still reference cuad.* after
sio(4) was deprecated by uart(4).

s/cuad/cuau/g/

PR: docs/171533
Reviewed by: imp
Approved by: cperciva (implicit)
MFC after: 3 weeks

Catch up with PHK's sio(4) cuaa->cuad rework [sys/dev/sio/sio.c rev. 1.456].

MF4S: Syncronise with Luigi's work in -stable.