build: don't clear recovery ramdisk

Clearing recovery ramdisk removes all files place there by the
device tree and all busybox symlinks placed there by recovery

Change-Id: I19e6164856a01a83a6e2c50ef96742edcb9f570f

Conflicts:
	core/Makefile
Allow Device specific ramdisk address

Change-Id: If0bb3d3a2b51f87a92c0b657fbc6d0277ce53532

Conflicts:
	core/Makefile
Deprecate BOARD_FORCE_RAMDISK_ADDRESS in favor of BOARD_MKBOOTIMG_ARGS.

Change-Id: Ib587f14cb45d752356beec3998a5b956f8b09efa
clockwwork recovery build fixes
fix BOARD_CUSTOM_BOOTIMG_MK
qcom_utils: Only define QCOM_BOARD_PLATFORMS if compiling kernel inline

	* If using prebuilt kernel KERNEL_OBJ/usr will not exist, thus
	  build will complain of dir missing during module compilation

	** Requires TARGET_USE_PREBUILT_KERNEL := true in BoardConfig for now

Signed-off-by: bmc08gt <bmc08gt.teamb00sted@gmail.com>
Change-Id: Iecd8c97e89504c60d2f01926318468ac7eb396f9