dmaengine: idxd: Remove unused idxd_(un)register_bus_type

idxd_register_bus_type() and idxd_unregister_bus_type() have been unused
since 2021's
commit d9e5481 ("dmaengine: dsa: move dsa_bus_type out of idxd driver
to standalone")

Remove them.

Signed-off-by: Dr. David Alan Gilbert <linux@treblig.org>
Reviewed-by: Fenghua Yu <fenghua.yu@intel.com>
Link: https://lore.kernel.org/r/20241221141635.69412-1-linux@treblig.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>

drivers/dma/idxd/idxd.h

@@ -725,8 +725,6 @@ static inline void idxd_desc_complete(struct idxd_desc *desc,
 				   &desc->txd, &status);
 }
 
-int idxd_register_bus_type(void);
-void idxd_unregister_bus_type(void);
 int idxd_register_devices(struct idxd_device *idxd);
 void idxd_unregister_devices(struct idxd_device *idxd);
 void idxd_wqs_quiesce(struct idxd_device *idxd);

drivers/dma/idxd/sysfs.c

@@ -1979,13 +1979,3 @@ void idxd_unregister_devices(struct idxd_device *idxd)
 		device_unregister(group_confdev(group));
 	}
 }
-
-int idxd_register_bus_type(void)
-{
-	return bus_register(&dsa_bus_type);
-}
-
-void idxd_unregister_bus_type(void)
-{
-	bus_unregister(&dsa_bus_type);
-}