- 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 r271394, r271398:

Add more register values to armreg.h and remove CPU_CONTROL_32BP_ENABLE
from asm.h as they were already defined in armreg.h.

Unify interrupts bit definition and usage. While here remove PSR_C_bit.

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

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

Pass the previously returned IRQ back to arm_get_next_irq() so that
the implementation can guarantee forward progress in the event of
a stuck interrupt or interrupt storm. This is especially critical
for fast interrupt handlers, as they can cause a hard hang in that
case. When first called, arm_get_next_irq() is passed -1.

Obtained from: Juniper Networks, Inc.

Support for the XScale PXA255 SoC as found on the Gumstix Basix and Connex
boards. This is enough to net-boot to multiuser.

Also supported is the SMSC LAN91C111 parts used on the netCF, netDUO and netMMC
add-on boards.

I'll be putting some instructions on how to boot this on the Gumstix boards
online soon.

This is still fairly rough and will be refined over time but I felt it was
better to get this out there where other people can help out.