Linux_HAL: Update ardupilot-master with linux tonealarm driver and unified storage class and working GPS ex. over linux.

Following are the major updates that will bring about by these commits:
Tonealarm support for HAL_Linux Boards (currently supports BBB based only).
Cape overlays for BBB to load PWM driver required for ToneAlarm.
Unified Storage class with FS and FRAM as two subclasses as per tridge's recommendation.