Add GSC firmware to generated factory images am: 11a86a2f70

Original change: https://googleplex-android-review.googlesource.com/c/device/common/+/26665910

Change-Id: I30a62b0d657f406601ff12d9bd511c9473dff485
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>