5261 libm should stop using synonyms.h

*** 25,36 ****
  /*
   * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
   * Use is subject to license terms.
   */
  
- #pragma weak exp10f = __exp10f
- 
  #include "libm.h"
  
  extern double exp10(double);
  
  float
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