[HAX] Allow per-target dtbTool

 * Revert this when fixed

Change-Id: I97ecb0448ae7bd5859454be290c5dde6248b2859
Allow mounting by partition name through edify
With more devices migrating over to emulated storage there is a need for
increased flexibility when mounting partitions. Edify scripts currently lack
the ability to mount emmc partitions by their labels, so busybox is used
as a reliable alternative.

This allows partitions to be mounted by name while still maintaining
compatibility with older recoveries.

To use define TARGET_SETS_FSTAB in the device's make files

Change-Id: I905740dd566f451b7ac48579a85e1b39a8cfd31a

Conflicts:
	core/Makefile
	tools/releasetools/edify_generator.py
	tools/releasetools/ota_from_target_files
build: edify: fix multiple device assert

Only generate one error message since multiple error message
will trigger a fail if the device does not match the first
assert

Change-Id: I1dc47cce10032eb28bbb808482b5ee9efc3b87bc

Conflicts:
	tools/releasetools/edify_generator.py
Enable QCOM_BSP_LEGACY flag for pre-8974 targets

Change-Id: I895f1b1cbad0d260e1bca87ccb61e6194de023fd

Conflicts:
	core/qcom_target.mk