Map uv_mode with get_uv_mode() for txk_sel
Map uv_mode with get_uv_mode() for txk_sel

Blocks with uv_mode == UV_CFL_PRED were pointing past
the end of intra_mode_to_tx_type_context[].

Change-Id: Ia638470ce46f914883bfc3e03f35706ef3d76352

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