graphics/ImageMagick6: update to 6.9.12-45

Changes:

• ImageMagick/ImageMagick#5028 6dca9a7
• eliminate Coverity defects 6ef3cb2
• eliminate arbitrary limit on CMS descriptions 2c452fc
• eliminate Coverity defects dcc7a67
• prep next release df41269
• eliminate coverity defects 68fe465
• check to see if ICC property exists before its created a5263ab
• pending release e8700b9
• revert 354943b
• Improved freetype error reporting. 05d5d26
• future: throw an exception if type cache cannot be acquired ae21b8c
• do not permit setting read-only properties (e.g. exif:*) 98abe54
• streaming interface must be allocated on the heap f2ab27b
• eliminate Coverity defects d6ccd35
• eliminate Coverity defects f730f49
• Added missing version check. 93bbd3a
• do not set ICC properties unless the value is non-null 5988721
• eliminate leak in Freetype streaming interface 980bfe2
• check for empty string not needed cbbcfa1
• Removed unused assignment. 44f42c2
• revert 65b99c4
• utilitze fstat() blocksize to set stream buffer size 7462d84
• eliminate Coverity defect c64edf6
• eliminate Coverity defects 3d50253
• eliminate compiler warning 8ca2579
• ImageMagick/ImageMagick#5034 dc070da
• prevent double free in Freetype streaming interface 212564a
• ImageMagick/ImageMagick#5037 1eb8339
• release e2d55af
• fix fill-opacity special case where the fill color alpha is fully transparent 83bd597
• eliminate compiler warning f82bd6a
• revert 8c9e882
• revert f49d606
• eliminate Coverity defects 5923cb3
• ImageMagick/ImageMagick#5027 6f7a9e2
• Corrected check. 17aa89f
• Revert local check. 8126c53
• fix memory leak in Freetype stream 8ead70f