media: v4l: fwnode: Remove unneeded forward declaration

Remove an unneeded declaration for struct fwnode_handle.
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Tested-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> # Renesas RZ/G2L SMARC
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

include/media/v4l2-fwnode.h

@@ -21,8 +21,6 @@
 
 #include <media/v4l2-mediabus.h>
 
-struct fwnode_handle;
-
 /**
  * struct v4l2_fwnode_endpoint - the endpoint data structure
  * @base: fwnode endpoint of the v4l2_fwnode