usb: Expand buffer size in usb_find_and_bind_driver()

The "generic_bus_%x_dev_%x" string which is printed into this buffer
can be up to 34 characters long ("generic_bus_12345678_dev_12345678").
The buffer would be clipped by snprintf() if both %x were at maximum
range. Make sure the buffer is long enough to cover such possibility.

Signed-off-by: Marek Vasut <marex@denx.de>
Reviewed-by: Simon Glass <sjg@chromium.org>

drivers/usb/host/usb-uclass.c

@@ -557,7 +557,7 @@ static int usb_find_and_bind_driver(struct udevice *parent,
 	struct usb_driver_entry *start, *entry;
 	int n_ents;
 	int ret;
-	char name[30], *str;
+	char name[34], *str;
 	ofnode node = usb_get_ofnode(parent, port);
 
 	*devp = NULL;