Generate extra userdata partition if needed

* To support variants of devices which may come in 16/32/64GB variants.

Change-Id: I74c32d8316f0450a1445fe95a95e5cabb7a9dd1b
Fixed building incrementals when "no separate recovery" is specified.

Change-Id: I1d7add44554ebc4b68dc09debdd0c0fb229061a9
Merge remote-tracking branch 'cm/cm-11.0' into cm-11.0-gcc48