WIP integrate with libosmocore in as far as msgb_alloc() works

Change-Id: I99617d217ab938ab57746445906b1af8902b5ff7
diff --git a/sysmoOCTSIM/hal/utils/include/utils.h b/sysmoOCTSIM/hal/utils/include/utils.h
index 1cf2699..52c0367 100644
--- a/sysmoOCTSIM/hal/utils/include/utils.h
+++ b/sysmoOCTSIM/hal/utils/include/utils.h
@@ -52,7 +52,9 @@
 /**
  * \brief Retrieve array size
  */
+#ifndef ARRAY_SIZE
 #define ARRAY_SIZE(a) (sizeof(a) / sizeof((a)[0]))
+#endif
 
 /**
  * \brief Emit the compiler pragma \a arg.