5261 libm should stop using synonyms.h

*** 28,38 ****
  
          .file "fmodf.s"
  
  #include "libm.h"
  LIBM_ANSI_PRAGMA_WEAK(fmodf,function)
- #include "libm_synonyms.h"
  
          ENTRY(fmodf)
          push    %rbp
          movq    %rsp,%rbp
          subq    $16,%rsp
--- 28,37 ----