rtemsbuildname.c: Fix missing prototype warnings

cpukit/rtems/src/rtemsbuildname.c

@@ -6,7 +6,7 @@
  */
 
 /*
- *  COPYRIGHT (c) 1989-2008.
+ *  COPYRIGHT (c) 1989-2013.
  *  On-Line Applications Research Corporation (OAR).
  *
  *  The license and distribution terms for this file may be
@@ -21,7 +21,25 @@
 #include <rtems/system.h>
 #include <rtems/rtems/types.h>
 
+/*
+ *  Undefine since this is normally a macro and we want a real body in
+ *  the library for other language bindings.
+ */
 #undef rtems_build_name
+
+/*
+ *  Prototype it to avoid warnings
+ */
+rtems_name rtems_build_name(
+  char C1,
+  char C2,
+  char C3,
+  char C4
+);
+
+/*
+ *  Now define a real body
+ */
 rtems_name rtems_build_name(
   char C1,
   char C2,