5261 libm should stop using synonyms.h

@@ -37,11 +37,11 @@
  *      if (n<0) n+=1
  *      z = scalbn(x,-n)
  *      LOG2(x) = n + (1/ln2)*log(x)
  */
 
-#pragma weak log2l = __log2l
+#pragma weak __log2l = log2l
 
 #include "libm.h"
 #include "longdouble.h"
 
 static const long double