sm8x50-userdebug: Add a generic build target for Qcom ARMv9 devboards am: bd765d63de am: 9e1cc1d2b7

Original change: https://android-review.googlesource.com/c/device/linaro/dragonboard/+/3022523

Change-Id: Iba368e82c283bf3b0907509b1253e6db4c4f826f
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>