Merge "fastboot: Introduce FASTBOOT_DEVICE alias for ANDROID_SERIAL...

Merge "fastboot: Introduce FASTBOOT_DEVICE alias for ANDROID_SERIAL environment variable" am: 929a665f

Original change: https://android-review.googlesource.com/c/platform/system/core/+/2621310



Change-Id: I4b88af8a45aa86464c5eb435148233320f5a5665
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>