imagemagick: security bump to 7.0.3-8

Fixes CVE-2016-9556 (Heap buffer overflow in IsPixelGray).

Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

package/imagemagick/imagemagick.hash

@@ -1,2 +1,2 @@
 # From http://www.imagemagick.org/download/releases/digest.rdf
-sha256 140b99f33a3326aed92132a7cd054ee962a6e2562064c68495640411aa4571d7  ImageMagick-7.0.3-7.tar.xz
+sha256 dc128b281c255d71d754934408d278b3ca314253103ca2501cd0b8d5ec98db74  ImageMagick-7.0.3-8.tar.xz

package/imagemagick/imagemagick.mk

@@ -4,7 +4,7 @@
 #
 ################################################################################
 
-IMAGEMAGICK_VERSION = 7.0.3-7
+IMAGEMAGICK_VERSION = 7.0.3-8
 IMAGEMAGICK_SOURCE = ImageMagick-$(IMAGEMAGICK_VERSION).tar.xz
 IMAGEMAGICK_SITE = http://www.imagemagick.org/download/releases
 IMAGEMAGICK_LICENSE = Apache-2.0