Cleanup pre function

Put variable declarations before any actual code to improve readability.

Signed-off-by: Olliver Schinagl <oliver@schinagl.nl>

sorting/ip-address.js

@@ -18,11 +18,17 @@
 
 jQuery.extend( jQuery.fn.dataTableExt.oSort, {
 	"ip-address-pre": function ( a ) {
-		if (!a) { return 0 }
 		var i, item;
-		var m = a.split("."),
-			n = a.split(":"),
-			x = "",
+		var m, n;
+		var x, xa;
+
+		if (!a) {
+			return 0
+		}
+
+		m = a.split(".");
+		n = a.split(":");
+		x = "";
 		xa = "";
 
 		if (m.length == 4) {