5261 libm should stop using synonyms.h

*** 57,67 ****
  / if x and y are finite and x**y = 0    _SVID_libm_err (underflow)
  / if x and y are finite and x**y = inf  _SVID_libm_err (overflow)
  
  #include "libm.h"
  LIBM_ANSI_PRAGMA_WEAK(pow,function)
- #include "libm_synonyms.h"
  #include "libm_protos.h"
  #include "xpg6.h"
  
  #undef fabs
  
--- 57,66 ----