This commit fixes issues with PAL games which use the incorrect feild
ordering.
We move all code that deals with indivudal fields from the indivudal
video plugins and VideoCommon and make VideoInterface always pass in
the start address of the whole XFB into VideoCommon.
They were named incorrectly in VideoInterface.h, but because nobody used
them outside of VideoInterface.cpp where they were decleared until now, this
hasn't been an issue.