GATT: Disable GATT over BR/EDR

Current stack does not handle dual-transport GATT well. When there are
multiple connections to a device on both transports, stack may not
operate the correct connection. So, as a walkaround, GATT over BR/EDR
should be disabled on Wear device considering their limited usage.

Test: gd/cert/run
Bug: 221946083
Bug: 225784319
Change-Id: I9a8f2455cb2aac813e4f1ea03d49b32c7ca61f10
(cherry picked from commit 41e9de3f1af7987b83ca997e5a02e9275f9a24af)