- 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

- Declare sparc64_memreg and sparc64_nmemreg in machine/ofw_mem.h.
- On startup print the total physical memory, instead of what we're told is
free by the firmware, to avoid astonishing users.

Use vm_paddr_t for physical addresses.

Add kernel dump support, based on the ia64 version (which was committed
as sparc64/sparc64/dump_machdep.c a while back).
Other than ia64 (which uses ELF), sparc64 uses a homegrown format for
the dumps (headers are required because the physical address and size of
the tsb must be noted, and because physical memory may be discontiguous);
ELF would not offer any advantages here.

Reviewed by: jake