staging/vme: Use pr_ printks in vme_pio2_core.c

The below checkpatch warnings was fixed,

-WARNING: Prefer pr_err(... to printk(KERN_ERR, ...

and added pr_fmt.
Signed-off-by: Toshiaki Yamane <yamanetoshi@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/vme/devices/vme_pio2_core.c

@@ -10,6 +10,8 @@
  * option) any later version.
  */
 
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
 #include <linux/module.h>
 #include <linux/moduleparam.h>
 #include <linux/types.h>
@@ -163,15 +165,13 @@ static int __init pio2_init(void)
 	int retval = 0;
 
 	if (bus_num == 0) {
-		printk(KERN_ERR "%s: No cards, skipping registration\n",
-			driver_name);
+		pr_err("No cards, skipping registration\n");
 		goto err_nocard;
 	}
 
 	if (bus_num > PIO2_CARDS_MAX) {
-		printk(KERN_ERR
-			"%s: Driver only able to handle %d PIO2 Cards\n",
-			driver_name, PIO2_CARDS_MAX);
+		pr_err("Driver only able to handle %d PIO2 Cards\n",
+		       PIO2_CARDS_MAX);
 		bus_num = PIO2_CARDS_MAX;
 	}