Fix function calls with named arguments for overloaded functions

test/libsolidity/semanticTests/functionCall/named_args_overload.sol

@@ -0,0 +1,32 @@
+contract C {
+    function f() public returns (uint) {
+        return 0;
+    }
+    function f(uint a) public returns (uint) {
+        return a;
+    }
+    function f(uint a, uint b) public returns (uint) {
+        return a+b;
+    }
+    function f(uint a, uint b, uint c) public returns (uint) {
+        return a+b+c;
+    }
+    function call(uint num) public returns (uint256) {
+        if (num == 0)
+            return f();
+        if (num == 1)
+            return f({a: 1});
+        if (num == 2)
+            return f({b: 1, a: 2});
+        if (num == 3)
+            return f({c: 1, a: 2, b: 3});
+
+        return 500;
+    }
+}
+// ----
+// call(uint256): 0 -> 0
+// call(uint256): 1 -> 1
+// call(uint256): 2 -> 3
+// call(uint256): 3 -> 6
+// call(uint256): 4 -> 500