Fix sao type context init values.
Fix sao type context init values.

The initialization slice types are in reverse order compared to the codes used
for slice types. They are BPI instead of IPB.

ultravideo/kvazaar,lu-zero/kvazaar,ultravideo/kvazaar,ultravideo/kvazaar,lu-zero/kvazaar,lu-zero/kvazaar,lu-zero/kvazaar,ultravideo/kvazaar,ultravideo/kvazaar