Disable config_doubleTapPowerGestureMode on Wear

Wear already has a logic to handle double-press gestures and the config
was already disabled under ag/30973796. Since the config was modified in
ag/30980545, this CL disables config_doubleTapPowerGestureMode on Wear
again since Wear has its own double tap power gesture.

Bug: 388347646
Test: manual
Flag: EXEMPT xml change only
Change-Id: If45fb406dd1462138d3c647d3a17af87276b1b1b