Add auto-mount and fake SD card support

Modified from:
http://git.android-x86.org/?p=platform/system/vold.git;a=commit;h=123572c9de7194344509d4094a397749daec0c59

Change-Id: I853dc273ff57623ec1e6d9a8e442b3d9702596ce
DirectVolume: handle discs with multiple major numbers

CFlag: BOARD_VOLD_DISC_HAS_MULTIPLE_MAJORS

Allows Direct Volume to handle discs with multiple major numbers.
Needed on Samsung Galaxy S II and variants.

For example:
mmcblk0p1 - 179:0
mmcblk0p2 - 179:1
mmcblk0p3 - 179:2
mmcblk0p4 - 256:0
mmcblk0p5 - 256:1

Change-Id: I633ac882a721cde25f0df779b4028efa6be15750

Conflicts:
	Android.mk