m7: make m7 the universal device tree

Change-Id: I65015c3b520a2631aa2e84121e938455d3b5d130
m7: move non-common stuff from m7-common to here

* Also move a couple common system props to m7-common

Change-Id: I1befe57f6e7cadb5cc23ef0b62604ac6d820fded