Merge "repack_bootimg: Support using local files as repack source" am: abf4051910 am: 029f536b90 am: 49b1c552b4

Original change: https://android-review.googlesource.com/c/platform/system/tools/mkbootimg/+/1856214

Change-Id: I02f8c242980535ad76180783853c82300a301fcd