Merge "Update retrofit_gki.sh for new init_boot plan" am: ac75382f8b am: 7782ab502d am: dd235e1a8f am: eba11b6120

Original change: https://android-review.googlesource.com/c/platform/system/tools/mkbootimg/+/1976890

Change-Id: Ibc71cf71d01d9ef409c6827d2dd22dba4b180ba8