staging: vchiq_arm: Remove extra struct vchiq_instance declaration

Additional declaration of struct vchiq_instance was introduced in the
commit 726e79f ("staging: vchiq_arm: pass vchiq instance to
service callbacks"). Drop the extra declaration.

Fixes: 726e79f ("staging: vchiq_arm: pass vchiq instance to service callbacks")
Signed-off-by: Umang Jain <umang.jain@ideasonboard.com>
Reviewed-by: Stefan Wahren <stefan.wahren@i2se.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Link: https://lore.kernel.org/r/20221221074047.233473-1-umang.jain@ideasonboard.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Author: Umang Jain

drivers/staging/vc04_services/include/linux/raspberrypi/vchiq.h

@@ -78,8 +78,6 @@ struct vchiq_service_params_kernel {
 	short version_min;   /* Update for incompatible changes */
 };
 
-struct vchiq_instance;
-
 extern int vchiq_initialise(struct vchiq_instance **pinstance);
 extern int vchiq_shutdown(struct vchiq_instance *instance);
 extern int vchiq_connect(struct vchiq_instance *instance);