- 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 r257334, r257336, r257337, r257338, r257341, r257342, r257343, r257370,
r257368, r257416

Hints-only devices should return BUS_PROBE_NOWILDCARD from their probe
methods.

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

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Add 32-bit support for Gxemul's oldtestmips machine emulation

Original work by: kan@

Correct an error in gxemul_disk_write(). It was issuing the command to
read from rather than write to the emulated disk.

Reviewed by: jmallett

Add a driver for the GXemul test machine's disk controller and disk devices.
Prefer it to using an md device in the GXEMUL kernel configuration.

Requested by: rwatson, theraven