configure: add missing OpenCL dependency to libavutil

Tested-by: wm4
Signed-off-by: James Almer <jamrial@gmail.com>

configure

@@ -3340,7 +3340,7 @@ avformat_deps="avcodec avutil"
 avformat_suggest="libm network"
 avresample_deps="avutil"
 avresample_suggest="libm"
-avutil_suggest="libm libdrm libmfx user32 vaapi videotoolbox wincrypt"
+avutil_suggest="libm libdrm libmfx opencl user32 vaapi videotoolbox wincrypt"
 postproc_deps="avutil gpl"
 postproc_suggest="libm"
 swresample_deps="avutil"