staging: comedi: ni_tio.h: remove unnecessary forward declarations

These struct forward declarations are not needed. Remove them.
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/comedi/drivers/ni_tio.h

@@ -19,10 +19,6 @@
 
 #include "../comedidev.h"
 
-/* forward declarations */
-struct mite_struct;
-struct ni_gpct_device;
-
 enum ni_gpct_register {
 	NITIO_G0_AUTO_INC,
 	NITIO_G1_AUTO_INC,