- 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 r260281, r260282, r260283, r260285

Implement OFW_BUS_MAP_INTR() in terms of the FDT PIC table

Reimplement fdt_intr_to_rl() in terms of OFW_BUS_MAP_INTR() and
OFW_BUS_CONFIG_INTR().

Use bus_space_map() rather than pmap_mapdev() in nexus_activate_resource(),
when running on FDT systems. Unmap memory in nexus_deactivate_resource().

Remove fdt_pic_table code from MIPS, PowerPC, and x86, as it is no longer
used by anything.

MFC r256870, r256898, r256899, r256900 (by nwhitehorn):

Standards-conformance and code deduplication:
- Use bus reference phandles in place of FDT offsets as IRQ domain keys
- Unify the identical macio/fdt/mambo OpenPIC drivers into one
- Be more forgiving (following ePAPR) about what we need from the device
tree to identify an OpenPIC
- Correctly map all IRQs into an interrupt domain
- Set IRQ_*_CONFORM for interrupts on an unknown PIC type instead of
failing attachment for that device.

Allow lots of interrupts (useful on multi-domain platforms) and do not
set device_quiet() on all devices attached under nexus(4).

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

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

Fix OF_finddevice error return value in case of FDT.

According to the open firmware standard, finddevice call has to return
a phandle with value of -1 in case of error.

This commit is to:
- Fix the FDT implementation of this interface (ofw_fdt_finddevice) to
return (phandle_t)-1 in case of error, instead of 0 as it does now.
- Fix up the callers of OF_finddevice() to compare the return value with
-1 instead of 0 to check for errors.
- Since phandle_t is unsigned, the return value of OF_finddevice should
be checked with '== -1' rather than '<= 0' or '> 0', fix up these cases
as well.

Reported by: nwhitehorn

Reviewed by: raj
Approved by: raj, nwhitehorn

Introduce PowerPC-specific helper routines for FDT.

Reviewed by: imp
Sponsored by: The FreeBSD Foundation