dragonboards: refactor graphics configs to independent fragments am: 6749c910f3 am: 9e382093fe

Original change: https://android-review.googlesource.com/c/device/linaro/dragonboard/+/2750582

Change-Id: Ieea84b8cfc90d526abb48530a9f3222a6df1d8d2
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>