usb: gadget: storage: Remove unused function pointer typedef fsg_routine_t

Remove the 'fsg_routine_t' typedef as it is not used.
Signed-off-by: Chen Lin <chen.lin5@zte.com.cn>
Link: https://lore.kernel.org/r/1613384130-3028-1-git-send-email-chen45464546@163.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/gadget/function/f_mass_storage.c

@@ -351,8 +351,6 @@ static inline struct fsg_dev *fsg_from_func(struct usb_function *f)
 	return container_of(f, struct fsg_dev, function);
 }
 
-typedef void (*fsg_routine_t)(struct fsg_dev *);
-
 static int exception_in_progress(struct fsg_common *common)
 {
 	return common->state > FSG_STATE_NORMAL;