cmake HAVE_OPJ_CIO_OPEN examples

vxl/vxl config/cmake/Modules/FindOpenJPEG2.cmake :46 

CHECK_FUNCTION_EXISTS("opj_cio_open" HAVE_OPJ_CIO_OPEN)

InsightSoftwareConsortium/ITK Modules/ThirdParty/VNL/src/vxl/config/cmake/Modules/FindOpenJPEG2.cmake :46 

CHECK_FUNCTION_EXISTS("opj_cio_open" HAVE_OPJ_CIO_OPEN)