Create MEDIA_ROUTING_CONTROL app op permission for proxy routing

The new permission allows holders of COMPANION_DEVICE_WATCH to use
MediaRouter2 to control the routing of other apps from the watch.
Users will grant the permission from a Special App Access setting.

Bug: 305919655
Bug: 192657812
Test: atest CtsMediaBetterTogetherTestCases
Change-Id: I204ddbf545c3e8952bd6bec1ef86bffadbe58cbd