Revert "hammerhead: fixups"

This reverts commit de4b5618a836488a2a70f8d198f16710580a9a3b.

PRODUCT_RESTRICT_VENDOR_FILES is a useless assignement, it only makes sense
when set to true. TARGET_PROVIDES_GPS_LOC_API is not used in the whole
android tree as hardware/qcom/gps does not exist anymore.

Change-Id: I18c944c7b86826a4789b74ddbb20718007d24aad