Merge "libdm: Add a helper function for creating placeholder devices." am:...

Merge "libdm: Add a helper function for creating placeholder devices." am: 3460b752 am: 1ab03512

Original change: https://android-review.googlesource.com/c/platform/system/core/+/2357843



Change-Id: I2ec63b5fc6676a86e0691ea25f459d58674c4c63
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>