gps: Prevent building from source

mako's GPS HAL is now a proprietary, but we still want to deploy
source for other devices. Set TARGET_PROVIDES_GPS_LOC_API to
prevent it from being built for this device

Change-Id: I40dc473b230b7d8887a2a5a38de22868afe77eb4
Merge branch 'cm-10.2' into martincz