[Pkg-gmagick-im-team] Bug#823750: Fix a SIGABRT in pdb file handling

[Bastien ROUCARIES]

    Fix a SIGABRT in pdb file handling

    bug: https://github.com/ImageMagick/ImageMagick/issues/148
    bug-ubuntu:
https://bugs.launchpad.net/ubuntu/+source/imagemagick/+bug/1556273
    origin: upstream,
https://github.com/ImageMagick/ImageMagick/commit/53c1dcd34bed85181b901bfce1a2322f85a59472
    bug-debian:  https://bugs.debian.org/823750