Make sure everybody wraps #include "config.h" in #ifdef HAVE_CONFIG_H

Original commit message from CVS:
* ext/ffmpeg/gstffmpeg.c:
* ext/ffmpeg/gstffmpegcodecmap.c:
* ext/ffmpeg/gstffmpegdec.c:
* ext/ffmpeg/gstffmpegenc.c:
* ext/ffmpeg/gstffmpegprotocol.c:
* ext/gdk_pixbuf/gstgdkanimation.c:
* ext/jpeg/gstjpeg.c:
* ext/libpng/gstpng.c:
* ext/mpeg2dec/perftest.c:
* ext/speex/gstspeex.c:
* gst-libs/gst/resample/dtos.c:
* gst/intfloat/gstintfloatconvert.c:
* gst/oneton/gstoneton.c:
* gst/rtjpeg/RTjpeg.c:
* gst/rtp/gstrtp.c:
* sys/dxr3/dxr3init.c:
* sys/glsink/gstgl_nvimage.c:
* sys/glsink/gstgl_pdrimage.c:
* sys/glsink/gstglsink.c:
* testsuite/gst-lint:
Make sure everybody wraps #include "config.h" in #ifdef HAVE_CONFIG_H

ext/ffmpeg/gstffmpeg.c

@@ -21,7 +21,9 @@
  * object definition and other useful things.
  */
 
+#ifdef HAVE_CONFIG_H
 #include "config.h"
+#endif
 #include <gst/gst.h>
 #ifdef HAVE_FFMPEG_UNINSTALLED
 #include <avcodec.h>

ext/ffmpeg/gstffmpegcodecmap.c

@@ -19,7 +19,9 @@
  * Boston, MA 02111-1307, USA.
  */
 
+#ifdef HAVE_CONFIG_H
 #include "config.h"
+#endif
 #include <gst/gst.h>
 #ifdef HAVE_FFMPEG_UNINSTALLED
 #include <avcodec.h>

ext/ffmpeg/gstffmpegdec.c

@@ -17,7 +17,9 @@
  * Boston, MA 02111-1307, USA.
  */
 
+#ifdef HAVE_CONFIG_H
 #include "config.h"
+#endif
 
 #include <assert.h>
 #include <string.h>

ext/ffmpeg/gstffmpegenc.c

@@ -17,7 +17,9 @@
  * Boston, MA 02111-1307, USA.
  */
 
+#ifdef HAVE_CONFIG_H
 #include "config.h"
+#endif
 
 #include <assert.h>
 #include <string.h>

ext/ffmpeg/gstffmpegprotocol.c

@@ -17,9 +17,11 @@
  * Boston, MA 02111-1307, USA.
  */
 
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
 #include <string.h>
 #include <errno.h>
-#include "config.h"
 #ifdef HAVE_FFMPEG_UNINSTALLED
 #include <avformat.h>
 #else