staging:rtl8192u: Rename file macro to avoid camel case - Coding Style

Simple rename of the preprosessor switch, protecting against multiple
inclusion of the header file. Change to clear the checkpatch coding style
issue.
Signed-off-by: John Whitmore <johnfwhitmore@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/rtl8192u/r8192U.h

@@ -15,8 +15,8 @@
  * project Authors.
  */
 
-#ifndef R819xU_H
-#define R819xU_H
+#ifndef R8192U_H
+#define R8192U_H
 
 #include <linux/compiler.h>
 #include <linux/module.h>