include: Switch to #pragma once pattern

Signed-off-by: Sylvain Munaut <tnt@246tNt.com>
diff --git a/src/gsm/milenage/milenage.h b/src/gsm/milenage/milenage.h
index a91e946..6fb779c 100644
--- a/src/gsm/milenage/milenage.h
+++ b/src/gsm/milenage/milenage.h
@@ -12,8 +12,7 @@
  * See README and COPYING for more details.
  */
 
-#ifndef MILENAGE_H
-#define MILENAGE_H
+#pragma once
 
 void milenage_generate(const u8 *opc, const u8 *amf, const u8 *k,
 		       const u8 *sqn, const u8 *_rand, u8 *autn, u8 *ik,
@@ -31,5 +30,3 @@
 		   u8 *res, u8 *ck, u8 *ik, u8 *ak, u8 *akstar);
 
 int milenage_opc_gen(u8 *opc, const u8 *k, const u8 *op);
-
-#endif /* MILENAGE_H */