- 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)

MFC r278303:

cxgbe(4): Add a minimal if_cxl module that pulls in the real driver as
a dependency. This ensures "ifconfig cxl<n> ..." does the right thing
even when it's run with no driver loaded.

if_cxl.ko is the tiniest module in /boot/kernel.

cxgbe(4): Add a minimal if_cxl module that pulls in the real driver as
a dependency. This ensures "ifconfig cxl<n> ..." does the right thing
even when it's run with no driver loaded.

if_cxl.ko is the tiniest module in /boot/kernel.

MFC after: 2 weeks