Re-style fdlibm to conform to jerry guidelines

* First re-style was done automatically by indent to minimize the
  chance of errors during rewrite.

* Manual changes were applied to non-critical places only (comments
  and spaces):
  * Replaced all tabs with spaces.
  * Fixed tab stops in formulae in function comments.
    (Note: ASCII art for math formulae (especially for super- and
    subscripts) is a terrible idea.)
  * Unified the style of function comments.
  * Moved some in-code comments to their right places, which indent
    couldn't handle.
  * Added spaces to formulae of in-code comments to make them more
    readable.
  * Added braces mandated by jerry style guidelines.
  * Added parentheses to multiline #ifdef.

JerryScript-DCO-1.0-Signed-off-by: Akos Kiss akiss@inf.u-szeged.hu

third-party/fdlibm/s_copysign.c

@@ -6,21 +6,20 @@
  *
  * Developed at SunSoft, a Sun Microsystems, Inc. business.
  * Permission to use, copy, modify, and distribute this
- * software is freely granted, provided that this notice 
+ * software is freely granted, provided that this notice
  * is preserved.
  * ====================================================
  */
 
-/*
- * copysign(double x, double y)
- * copysign(x,y) returns a value with the magnitude of x and
+/* copysign(x,y) returns a value with the magnitude of x and
  * with the sign bit of y.
  */
 
 #include "fdlibm.h"
 
-double copysign(double x, double y)
+double
+copysign (double x, double y)
 {
-	__HI(x) = (__HI(x)&0x7fffffff)|(__HI(y)&0x80000000);
-        return x;
-}
+  __HI (x) = (__HI (x) & 0x7fffffff) | (__HI (y) & 0x80000000);
+  return x;
+} /* copysign */