5261 libm should stop using synonyms.h

@@ -25,12 +25,12 @@
 /*
  * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
  * Use is subject to license terms.
  */
 
-#pragma weak logb = __logb
-#pragma weak _logb = __logb
+#pragma weak __logb = logb
+#pragma weak _logb = logb
 
 #include "libm.h"
 #include "xpg6.h"       /* __xpg6 */
 #define _C99SUSv3_logb  _C99SUSv3_logb_subnormal_is_like_ilogb