The old name was a bit misleading. AXP173 is sort of the lowest common
denominator of a series of related chips. The M3K uses an AXP192 which
has a few extra features vs. the AXP173.
New voltage regulator stuff was added for the sake of the Shanling Q1
native port (that player also uses an AXP192).
Change-Id: Id0c162c23094bb03d13fae2d6c332e3047968d6e
