vo_corevideo.h: Add standard multiple inclusion guards

git-svn-id: svn://svn.mplayerhq.hu/mplayer/trunk@32210 b3059339-0415-0410-9bf9-f77b7e298cf2

libvo/vo_corevideo.h

@@ -20,6 +20,9 @@
  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  */
 
+#ifndef MPLAYER_VO_COREVIDEO_H
+#define MPLAYER_VO_COREVIDEO_H
+
 #import <Cocoa/Cocoa.h>
 #import <QuartzCore/QuartzCore.h>
 #import <Carbon/Carbon.h>
@@ -108,3 +111,5 @@
 - (void) mouseEvent: (NSEvent *) theEvent;
 - (void) check_events;
 @end
+
+#endif /* MPLAYER_VO_COREVIDEO_H */