AOSP: Correct device type for dual mode peers

Currently, device type determination logic is fuzzy in the stack.
Dual mode devices are incorrectly classified as BR/EDR. We should
reference the remote capabilities and set the peer device type to
DUAL if BR/EDR and BLE transports are both supported.

Bug: 186097823
Tag: #stability
Test: cert/run, manual device type testing (with and without gd)

Change-Id: Ibe4e02eea2a715be01457f8e48abfb846f25c81a