USB: Extend and neaten dbg macros

Add format/argument validation for #ifndef DEBUG dbg macro
Neaten dbg macro definitions

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/include/linux/usb.h b/include/linux/usb.h
index ad50fc8..3492abf 100644
--- a/include/linux/usb.h
+++ b/include/linux/usb.h
@@ -1566,14 +1566,18 @@
 extern void usb_unregister_notify(struct notifier_block *nb);
 
 #ifdef DEBUG
-#define dbg(format, arg...) printk(KERN_DEBUG "%s: " format "\n" , \
-	__FILE__ , ## arg)
+#define dbg(format, arg...)						\
+	printk(KERN_DEBUG "%s: " format "\n", __FILE__, ##arg)
 #else
-#define dbg(format, arg...) do {} while (0)
+#define dbg(format, arg...)						\
+do {									\
+	if (0)								\
+		printk(KERN_DEBUG "%s: " format "\n", __FILE__, ##arg); \
+} while (0)
 #endif
 
-#define err(format, arg...) printk(KERN_ERR KBUILD_MODNAME ": " \
-	format "\n" , ## arg)
+#define err(format, arg...)					\
+	printk(KERN_ERR KBUILD_MODNAME ": " format "\n", ##arg)
 
 /* debugfs stuff */
 extern struct dentry *usb_debug_root;