USB: handle pci_name() being const

This changes usb_create_hcd() to be able to handle the fact that
pci_name() has changed to a constant string.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/include/linux/usb.h b/include/linux/usb.h
index c08689e..cee7fbb 100644
--- a/include/linux/usb.h
+++ b/include/linux/usb.h
@@ -293,7 +293,7 @@
 struct usb_bus {
 	struct device *controller;	/* host/master side hardware */
 	int busnum;			/* Bus number (in order of reg) */
-	char *bus_name;			/* stable id (PCI slot_name etc) */
+	const char *bus_name;		/* stable id (PCI slot_name etc) */
 	u8 uses_dma;			/* Does the host controller use DMA? */
 	u8 otg_port;			/* 0, or number of OTG/HNP port */
 	unsigned is_b_host:1;		/* true during some HNP roleswitches */