Fix wifi startup timing issue

Bug: 17358965
Change-Id: Iacafcf1a1a9fed9755912b591eacdefd6992b088
remove /dev/diag node

Bug: 18203257
Change-Id: I7b9a2bdf0df6511317d59aa13fc187ab38795481
merge in lmp-release history after reset to lmp-dev
merge in lmp-release history after reset to lmp-dev