PCI: mvebu: Remove unused busn member

The busn member of struct mvebu_pcie is unused, so drop it.

Link: https://lore.kernel.org/r/20220905192310.22786-5-pali@kernel.org
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Cc: Thomas Petazzoni <thomas.petazzoni@bootlin.com>

drivers/pci/controller/pci-mvebu.c

@@ -87,7 +87,6 @@ struct mvebu_pcie {
 	struct resource io;
 	struct resource realio;
 	struct resource mem;
-	struct resource busn;
 	int nports;
 };