Add dirgroup for trusty genrule am: 21157a4bac

Original change: https://android-review.googlesource.com/c/trusty/app/confirmationui/+/3304636

Change-Id: Idec224dfec25b5ad7c306f65a32c06d0e8abbae5
Signed-off-by: Automerger Merge Worker <[email protected]>