IA2: Break out l2cap psm constants into own file am: 80205b6d am: d5a8260f am: fd1392c2

Original change: https://android-review.googlesource.com/c/platform/packages/modules/Bluetooth/+/2779207



Change-Id: I4b67e4d9e6726f19992865731ee7847d2a1e86c8
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>