virtio: pci: use correct type in virtio_pci_bind()

For printing as %u we should use an unsigned int.
Signed-off-by: NHeinrich Schuchardt <xypron.glpk@gmx.de>
Reviewed-by: NBin Meng <bmeng.cn@gmail.com>

drivers/virtio/virtio_pci_legacy.c

@@ -277,7 +277,7 @@ static int virtio_pci_notify(struct udevice *udev, struct virtqueue *vq)
 
 static int virtio_pci_bind(struct udevice *udev)
 {
-	static int num_devs;
+	static unsigned int num_devs;
 	char name[20];
 
 	/* Create a unique device name for PCI type devices */