Add /dev permissions to dynamic sensor README.md . am: 3493565708 am: 0c8d140c5c

Original change: https://googleplex-android-review.googlesource.com/c/platform/hardware/libhardware/+/17866052

Change-Id: Ia52c1c97ccd8f817e221a539543a763e0ca7d8cf
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>