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

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

Change-Id: Ic17049090abf87693c1f4253d13f9ab904fb5679
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>