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_fabs.c

@@ -6,19 +6,19 @@
  *
  * 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.
  * ====================================================
  */
 
-/*
- * fabs(x) returns the absolute value of x.
+/* fabs(x) returns the absolute value of x.
  */
 
 #include "fdlibm.h"
 
-double fabs(double x)
+double
+fabs (double x)
 {
-	__HI(x) &= 0x7fffffff;
-        return x;
-}
+  __HI (x) &= 0x7fffffff;
+  return x;
+} /* fabs */