5261 libm should stop using synonyms.h

@@ -25,11 +25,11 @@
 /*
  * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
  * Use is subject to license terms.
  */
 
-#pragma weak ilogb = __ilogb
+#pragma weak __ilogb = ilogb
 
 #include "libm.h"
 #include "xpg6.h"       /* __xpg6 */
 
 #if defined(__x86)