Memory leak

(cherry picked from commit 9edb299ad1acfb8a4b330d30cd1e6749a60df5ab)

Source commit: a573974d96406e0eee1f66261655d36649b06e41

source/putty/sshecc.c

@@ -49,7 +49,9 @@ static void finalize_common(struct ec_curve * curve)
 
 static void finalize_wcurve(struct ec_curve *curve)
 {
-    // TODO
+    ecc_weierstrass_curve_free(curve->w.wc);
+    ecc_weierstrass_point_free(curve->w.G);
+    mp_free(curve->w.G_order);
     finalize_common(curve);
 }