Fix chroma frame size boundary check
Fix chroma frame size boundary check

When chroma plane size is half of luma plane,
chroma plane's mi should correspond to even luma mi.

In loop filter bitmask, previous boundary check says out of bound
if frame size is not even. Indeed we still need to filter this chroma
position. Therefore the boundary condition check needs to be
separated for luma and chroma planes.

Use pixel frame size instead of mi_rows and mi_cols

BUG=aomedia:1922

Change-Id: I42025acf10527a587613582e17e8b310f9174301

GrokImageCompression/aom,GrokImageCompression/aom,GrokImageCompression/aom,GrokImageCompression/aom,GrokImageCompression/aom,GrokImageCompression/aom