- 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 r276162: Don't assume required FDT properties are present.

MFC r275779, r275963, r276101, r276161, r276297:

Move ofw_cpu.c to sys/dev/ofw so that it can be used by other
architectures.

Add driver for CPU frequency/voltage control on the Raspberry Pi.

On initialization, do not use bcm_mbox_intr() to read the pending messages.
This fixes the hang that happens on boot while initializing the cpufreq on
Raspberry Pi.

Move ofw_cpu.c to sys/dev/ofw so that it can be used by other
architectures.

Differential Revision: https://reviews.freebsd.org/D1307
Reviewed by: jhibbits

Move Open Firmware device root on PowerPC, ARM, and MIPS systems to
a sub-node of nexus (ofwbus) rather than direct attach under nexus. This
fixes FDT on x86 and will make coexistence with ACPI on ARM systems easier.
SPARC is unchanged.

Reviewed by: imp, ian

Fix error in r252115: space for the softc needs to be allocated. This
seemed to be working by chance on most systems.

Cache the Open Firmware CPU properties at attach time, so we don't always
enter it at runtime to get static data.

- There's no need to overwrite the default device method with the default
one. Interestingly, these are actually the default for quite some time
(bus_generic_driver_added(9) since r52045 and bus_generic_print_child(9)
since r52045) but even recently added device drivers do this unnecessarily.
Discussed with: jhb, marcel
- While at it, use DEVMETHOD_END.
Discussed with: jhb
- Also while at it, use __FBSDID.

Introduce support for cpufreq on PowerPC with the dynamic frequency
switching capabilities of the MPC7447A and MPC7448.