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 tgamma = __tgamma
+#pragma weak __tgamma = tgamma
 
 /* INDENT OFF */
 /*
  * True gamma function
  * double tgamma(double x)