Merge "Fix ota build error when using boot variable files" am: 775187f9 am: fc7314a6

Original change: https://android-review.googlesource.com/c/platform/build/+/2265664



Change-Id: I2e1239c9c5d89229424439e15d1dc1f323274cbf
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>