Unbreak build.

Index: plugins/linux-v4l2/v4l2-controls.c
--- plugins/linux-v4l2/v4l2-controls.c.orig
+++ plugins/linux-v4l2/v4l2-controls.c
@@ -17,7 +17,11 @@ along with this program.  If not, see <http://www.gnu.
 
 #include <fcntl.h>
 
+#if defined(__OpenBSD__)
+#include <sys/videoio.h>
+#else
 #include <linux/videodev2.h>
+#endif
 #include <libv4l2.h>
 
 #include "v4l2-controls.h"
