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

- Don't set CAS_PCS_DATAPATH to anything except CAS_PCS_DATAPATH_SERDES
on Cassini using the external PCS SERDES otherwise unaligned access
traps and other strange effects happen with some machines. Don't touch
the MIF which is unused in that case either. These changes require the
PHY type to use to be determined via the OFW device tree or from the
VPD in machines without the former.
- Disable the SERDES pins of Saturn when not used in order to save power
and ensure they are enabled otherwise.
- In cas_attach() use the correct register offset for CAS_PCS_CONF_EN.
- Add some bus space barriers missing in the PCS code path.

These changes make the Sun GigaSwift Ethernet 1.0 MMF cards as well as
the on-board interfaces found in Sun Fire B100s Blade Server work.

PR: 144867

Add cas(4), a driver for Sun Cassini/Cassini+ and National Semiconductor
DP83065 Saturn Gigabit Ethernet controllers. These are the successors
of the Sun GEM controllers and still have a similar but extended transmit
logic. As such this driver is based on gem(4).
Thanks to marcel@ for providing a Sun Quad GigaSwift Ethernet UTP (QGE)
card which was vital for getting this driver to work on architectures
not using Open Firmware.

Approved by: re (kib)
MFC after: 2 weeks