Move device dependent functionality to libwifi-hal

Bug: 29418968
Change-Id: I0fa3047972c57af7128ce6384b62960f6f017d93
Test: wifi works/unittests pass on bullhead
7 files changed
tree: b06882f46a46c89b8320d6b4e4b5eb89eacbad6c
  1. libwifi_hal/
  2. libwifi_system/
  3. service/
  4. tests/