Remove unused avdevice.h header file; add config.h which is used.

git-svn-id: file:///var/local/repositories/ffmpeg/trunk@13006 9553f0bf-9b14-0410-a0b8-cfaf0461ba5b

libavdevice/alldevices.c

@@ -18,7 +18,7 @@
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 #include "avformat.h"
-#include "avdevice.h"
+#include "config.h"
 
 #define REGISTER_MUXER(X,x) { \
           extern AVOutputFormat x##_muxer; \