libre: netpbm: update to 10.73.36 by syncing with Arch Linux
    
    According to Wikipedia: "GIF images are compressed using the
    Lempel–Ziv–Welch (LZW) lossless data compression technique to reduce
    the file size without degrading the visual quality. This compression
    technique was patented in 1985. Controversy over the licensing
    agreement between the software patent holder, Unisys, and CompuServe
    in 1994 spurred the development of the Portable Network Graphics (PNG)
    standard. By 2004 all the relevant patents had expired."[1].
    
    So we can safely stop removing GIF related code on the basis of
    patents alone.
    
    [1]https://en.wikipedia.org/wiki/GIF
    
    Signed-off-by: Denis 'GNUtoo' Carikli <GNUtoo@cyberdimension.org>