rename sub_hfyu_median_prediction_int16 to sub_hfyu_median_pred_int16

This makes the naming more consistent with the 8bit variant

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
rename add_hfyu_median_prediction_int16 to add_hfyu_median_pred_int16

This makes the naming more consistent with the 8bit variant

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
rename add_hfyu_left_prediction_int16 to add_hfyu_left_pred_int16

This makes the naming more consistent with the 8bit variant

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>