[HAX] Allow per-target dtbTool

 * Revert this when fixed

Change-Id: I97ecb0448ae7bd5859454be290c5dde6248b2859

build: Default to dtbToolCM

* The default dtbTool isn't the correct module name for the module that
  actually lives in device/qcom/common/dtbtool

Change-Id: I80b427e3652b99742573bc4d2829e51645a8822b

Conflicts:
	core/generate_extra_images.mk
qcom_utils: Make "is-vendor-board-platform,XX" depend on BOARD_HAS_XX_HARDWARE

Prevent qc's code from wrongly kicking in for AOSP-derived
configurations