Remove @RequiresPermission annotation from checkMediaRoutingControlPermission

Non-functional change. Method checkMediaRoutingControlPermission should not require
MEDIA_ROUTING_CONTROL permission as it checks whether this permission is
granted to the calling app.

Bug: b/325755852
Test: NA
Change-Id: I6533fb7bcc0b99c8989bf2fbb304a1f3f27dcfe8