staging: prima: Get MAC address from WCNSS platform device

* Tools can set the value easily from userspace.

Change-Id: Ied4e4f1a4da0c58aa9bc07ee38aebed637eaeda3
msm: HTC: s4: update prima config

Change-Id: Idab2c48b94975521bbf879130e52a7dab28b86f2