Also, splits the sub_tx_size_map array into inter and intra
in order to enable the new 4:1 transforms for inter and
intra separately.
Includes refactoring such as removing the intra_tx_size_cat_lookup
array since it is unnecessary, and consolidating the
max_txsize_rect_lookup array for convenience.

Change-Id: I112553bab612dafb973611c87f36a43e1ac4be85