Remove unneeded call to png_set_swap_alpha

Alpha byte swapping is done in twin_premultiply_alpha(), so
the PNG processing overhead can be reduced by removing the
png_set_swap_alpha() call in twin_png_to_pixmap() and adjusting
twin_premultiply_alpha().

Signed-off-by: Geoff Levand <geoff@infradead.org>
2 files changed