[automerger skipped] Check for system_other existence in recovery mode as well. am: ddf27738af am: c19c71339d -s ours

am skip reason: Change-Id I1884755aad2a8d37f540dbee73c7c7baab2759e7 with SHA-1 ddf27738af is in history

Original change: https://googleplex-android-review.googlesource.com/c/platform/system/update_engine/+/11796618

Change-Id: I4bf70ae2df437972115011922b30419bfc694b6b