- Copy stable/10@296371 to releng/10.3 in preparation for 10.3-RC1
builds.
- Update newvers.sh to reflect RC1.
- Update __FreeBSD_version to reflect 10.3.
- Update default pkg(8) configuration to use the quarterly branch.

Approved by: re (implicit)

Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

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