Enable boot.img creation

In order to build a boot.img, the following build variables
need to be defined in the build.config file:

As we finalize where all the prebuilts will get delivered to,
some of the below may become unnecessary.

BUILD_BOOT_IMG=1
MKBOOTIMG_PREBUILT=<path to mkbootimg.py>
GKI_RAMDISK_PREBUILT_BINARY=<path to GKI ramdisk prebuilt>
VENDOR_RAMDISK_PREBUILT_BINARY=<path to vendor ramdisk prebuilt>
KERNEL_BINARY=<name of kernel file, eg. Image.lz4, Image.gz etc>
BOOT_IMAGE_HEADER_VERSION=<boot image header version>

Change-Id: I191c39911b53cef17c01bd4adb8dd4f5a2e17aee
1 file changed