vold: allow non-vfat devices to be used as ASEC

CM supports alternative file systems (which some devices specify
in the fstab as 'auto').

Change-Id: I7e78fe87a7efc49d6749d5892107085d55156cce
vold: Honor mount options for ext4 mounts

Conflicts:
	Ext4.cpp
	Ext4.h
	Volume.cpp

Change-Id: Ie77e0d402c2c16d544251f7fdaeaad34d030d121