5261 libm should stop using synonyms.h

@@ -28,11 +28,10 @@
 
         .file "ilogb.s"
 
 #include "libm.h"
 LIBM_ANSI_PRAGMA_WEAK(ilogb,function)
-#include "libm_synonyms.h"
 #include "xpg6.h"
 
         .data
         .align  8
 two52:  .long   0x0,0x43300000  / 2**52