buildinfo: only set ro.build.product on non-unified devices

Change-Id: I5dccba2172dade3dacc55d832a2042fce306b5f5
core: Enable -mcpu=cortex-a9 flag for Cortex-A9 cpu variant

Change-Id: I9294a518bcdc21ccbae72eadd9f3c1a12982d028
Merge remote-tracking branch 'cm/cm-12.0' into cm-12.0