Add header guards.

Change-Id: Ia5056080391a4dae7e12e53fd97c9cc1b3452874
diff --git a/libupgrade/hmx_upgrade_nvram.h b/libupgrade/hmx_upgrade_nvram.h
index 6cf834c..b0f8588 100644
--- a/libupgrade/hmx_upgrade_nvram.h
+++ b/libupgrade/hmx_upgrade_nvram.h
@@ -32,6 +32,8 @@
  * @file hmx_upgrade_nvram.h

  */

 

+#ifndef HMX_UPGRADE_NVRAM_H_

+#define HMX_UPGRADE_NVRAM_H_

 /*******************************************************************/

 /**************************** Header Files**************************/

 /*******************************************************************/

@@ -339,4 +341,5 @@
 /* End global function prototypes */

 

 

+#endif  // HMX_UPGRADE_NVRAM_H_

 /*@}*/