dragonboards: Enable system_dlkm partition support am: b0274055b8 am: c2014ed3b3

Original change: https://android-review.googlesource.com/c/device/linaro/dragonboard/+/2686346

Change-Id: I4d564334135c616e8616b93c9da6fdaf2e03fa6a
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>