avutil/opencl: don't include config.h

It's not an installed header.
Tested-by: Thilo Borgmann <thilo.borgmann@mail.de>
Tested-by: Wei Gao <highgod0401@gmail.com>
Reviewed-by: Michael Niedermayer <michaelni@gmx.at>
Signed-off-by: James Almer <jamrial@gmail.com>

configure

@@ -1642,7 +1642,6 @@ HEADERS_LIST="
     asm_types_h
     cdio_paranoia_h
     cdio_paranoia_paranoia_h
-    CL_cl_h
     dev_bktr_ioctl_bt848_h
     dev_bktr_ioctl_meteor_h
     dev_ic_bt8xx_h
@@ -4775,7 +4774,6 @@ check_func_headers glob.h glob
 enabled xlib &&
     check_func_headers "X11/Xlib.h X11/extensions/Xvlib.h" XvGetPortAttribute -lXv -lX11 -lXext
 
-check_header cl/cl.h
 check_header direct.h
 check_header dlfcn.h
 check_header dxva.h

libavutil/opencl.h

@@ -32,11 +32,10 @@
 #ifndef LIBAVUTIL_OPENCL_H
 #define LIBAVUTIL_OPENCL_H
 
-#include "config.h"
-#if HAVE_CL_CL_H
-#include <CL/cl.h>
-#else
+#ifdef __APPLE__
 #include <OpenCL/cl.h>
+#else
+#include <CL/cl.h>
 #endif
 #include <stdint.h>
 #include "dict.h"