Clean up style in BLE White List code

* Remove unused code
* Update BgConnHash to return size_t for hashcode
* Change BLE scan_int and scan_win to uint16_t according to spec

Bug: 111562702
Test: SL4A BLE test and manual with BLE mouse
Change-Id: Ieff3acbfaa95b7d804e57021d562218d9fbe42cc