imagemagick: disable opencl

* it can try to use host paths like:
  -lOpenCL -L/usr/lib/nvidia
  -lCL -L/usr/lib/nvidia
  -lclparser -L/usr/lib/nvidia
  ERROR: This autoconf log indicates errors, it looked at host include and/or library paths while determining system capabilities.

Signed-off-by: Martin Jansa <Martin.Jansa@gmail.com>

meta-oe/recipes-support/imagemagick/imagemagick_6.7.5.bb

@@ -5,7 +5,7 @@ LIC_FILES_CHKSUM = "file://LICENSE;md5=944f66dcedc98d5a4e5d964bd3b32e7b"
 # FIXME: There is much more checked libraries. All should be added or explicitly disabled to get consistent results.
 DEPENDS = "lcms bzip2 jpeg libpng librsvg tiff zlib fftw"
 
-PR = "r4"
+PR = "r5"
 
 PATCHSET = "6"
 SRC_URI = "ftp://ftp.nluug.nl/pub/ImageMagick/ImageMagick-${PV}-${PATCHSET}.tar.bz2 \
@@ -21,7 +21,7 @@ inherit autotools binconfig pkgconfig
 
 # xml disabled because it's using xml2-config --prefix to determine prefix which returns just /usr with our libxml2
 # if someone needs xml support then fix it first
-EXTRA_OECONF = "--program-prefix= --without-x --without-freetype --without-perl --disable-openmp --without-xml"
+EXTRA_OECONF = "--program-prefix= --without-x --without-freetype --without-perl --disable-openmp --without-xml --disable-opencl"
 
 FILES_${PN} += "${libdir}/ImageMagick-${PV}/modules-Q16/*/*.so \
                 ${libdir}/ImageMagick-${PV}/modules-Q16/*/*.la \