opengl: importer: forward-declare structs

interop and picture_t definition are not needed in the header.

modules/video_output/opengl/importer.c

@@ -23,6 +23,7 @@
 #endif
 
 #include <vlc_common.h>
+#include <vlc_picture.h>
 
 #include "importer_priv.h"
 

modules/video_output/opengl/importer.h

@@ -25,14 +25,14 @@
 # include "config.h"
 #endif
 
-#include <vlc_picture.h>
-#include "interop.h"
+typedef struct picture_t picture_t;
 
 /**
  * An importer uses an interop to convert picture_t to a valid vlc_gl_picture,
  * with all necessary transformations computed.
  */
 struct vlc_gl_importer;
+struct vlc_gl_interop;
 
 struct vlc_gl_importer *
 vlc_gl_importer_New(struct vlc_gl_interop *interop);