- Copy stable/10@285827 to releng/10.2 in preparation for 10.2-RC1
builds.
- Update newvers.sh to reflect RC1.
- Update __FreeBSD_version to reflect 10.2.
- Update default pkg(8) configuration to use the quarterly branch.[1]

Discussed with: re, portmgr [1]
Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

MFC r261342

Add hwpmc(4) support for the PowerPC 970 class processors, direct events.
This also fixes asserts on removal of the module for the mpc74xx.

The PowerPC 970 processors have two different types of events: direct events
and indirect events. Thus far only direct events are supported. I included
some documentation in the driver on how indirect events work, but support is
for the future.

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

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

Fix hwpmc(4) for 32-bit PowerPC.

Refactor PowerPC hwpmc(4) driver into generic and specific. More refactoring
will likely be done as more drivers are added, since AIM-compatible processors
have similar PMC configuration logic.