Make hidl.manager optional in default device matrix am: 32121aecfd

Original change: https://android-review.googlesource.com/c/platform/system/libhidl/+/2243537

Change-Id: Ie0f007f3cbffb8135cad2584d75f3352baf1cce1
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>