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 hypot = __hypot
  
  /* INDENT OFF */
  /*
   * Hypot(x, y)
   * by K.C. Ng for SUN 4.0 libm, updated 3/11/2003.
--- 25,35 ----
  /*
   * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
   * Use is subject to license terms.
   */
  
! #pragma weak __hypot = hypot
  
  /* INDENT OFF */
  /*
   * Hypot(x, y)
   * by K.C. Ng for SUN 4.0 libm, updated 3/11/2003.