Merge "system/gd: Enforce -Wmissing-prototypes" into main am: fa55a6fb am: d2da2f08

Original change: https://android-review.googlesource.com/c/platform/packages/modules/Bluetooth/+/3507143



Change-Id: I8fb358398a61e0bc1a808d3459a1333a87d9049a
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>