5261 libm should stop using synonyms.h

*** 28,38 ****
  
          .file "log10l.s"
  
  #include "libm.h"
  LIBM_ANSI_PRAGMA_WEAK(log10l,function)
- #include "libm_synonyms.h"
  
          ENTRY(log10l)
          fldlg2  
          fldt    4(%esp)                 / st = arg, st(1) = log10(2)
          fyl2x                           / st = log10(arg) = log10(2)*log2(arg)
--- 28,37 ----