Edify: Add AssertSomeBaseband

Allow releasetools.py to assert a baseband version. Works just like
AssertSomeBootloader.

Change-Id: Ic8eb341cef1d777d983be25ba21a3bc545819c29
ota_from_target_files: Validate signatures after possible data wipe

If the data is being wiped, we want to validate the signature after
this step. This is also a good check that the data wipe succeeded.

Change-Id: Iaecfddfb2010944de0c97e7bb21d8e581f20deec
core: arm: Add support for GCC 4.8 and 4.9

Change-Id: I96bffffb4b0e16ef5bcedc85dedc70ca3dc2182f
core: arm: Use -O3 optimization inside TARGET_arm_CFLAGS

Change-Id: I224b62b3dada874d00a90258a1dcffcea09bc029