Merge "Document emergency case for setAllowedNetworkTypeBitmap" am: e9fb347e0b am: fd6c4f5f5d

Original change: https://android-review.googlesource.com/c/platform/hardware/interfaces/+/1531900

MUST ONLY BE SUBMITTED BY AUTOMERGER

Change-Id: I236a749c4626e2672a82621925870d8ecc78ce0c