5261 libm should stop using synonyms.h

*** 25,35 ****
  /*
   * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
   * Use is subject to license terms.
   */
  
! #pragma weak tanhl = __tanhl
  
  /*
   * tanhl(x) returns the hyperbolic tangent of x
   *
   * Method :
--- 25,35 ----
  /*
   * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
   * Use is subject to license terms.
   */
  
! #pragma weak __tanhl = tanhl
  
  /*
   * tanhl(x) returns the hyperbolic tangent of x
   *
   * Method :