Fix an SEGV in sun file handling
This is from two upstream patches.
Bug: http://www.imagemagick.org/discourse-server/viewtopic.php?f=3&t=26848
Bug-debian: https://bugs.debian.org/823750
Origin: upstream,
https://github.com/ImageMagick/ImageMagick/commit/bd96074b254c6607a0f7731e59f923ad19d5a46d,
https://github.com/ImageMagick/ImageMagick/commit/450bd716ed3b9186dd10f9e60f630a3d9eeea2a4
