build: Add QCOM target-specific config

 * Needed to support global DirectTract config on legacy targets
 * Let's also eliminate some boilerplate

Change-Id: I736c10a5e7e1f3d1e0de9e60f29b60add276f151

Conflicts:

	core/config.mk
qcom_utils: Update list of QCOM_BOARD_PLATFORMS

Add msm8226 (Moto G) and other upcoming platforms
Change-Id: Icf895cbcf86791ca800636a1c0893b3a905a27a0

Conflicts:

	core/qcom_utils.mk
build: Fix cflags for QC targets

Change-Id: I2281bec3afb4d80e80845718d880dc24ef7baf32