video: Fix line padding calculation for 16 and 24 BPP bitmaps
Each row in the pixel array in the bitmap file is padded
if necessary so the row size is always a multiple of 4 bytes.
In current code the complement of row size to a multiple of
4 bytes is further unnecessarily multiplied by the pixel size.
This results in incorrect displaying of bitmaps having row size
that is not a multiple of 4 bytes. Fix this by removing
the unnecessary multiplication.