sv: support tasks and functions within packages

tests/verilog/package_task_func.sv

@@ -0,0 +1,30 @@
+package P;
+    localparam Y = 2;
+    localparam X = Y + 1;
+    task t;
+        output integer x;
+        x = Y;
+    endtask
+    function automatic integer f;
+        input integer i;
+        f = i * X;
+    endfunction
+    function automatic integer g;
+        input integer i;
+        g = i == 0 ? 1 : Y * g(i - 1);
+    endfunction
+    localparam Z = g(4);
+endpackage
+
+module top;
+    integer a;
+    initial P::t(a);
+    integer b = P::f(3);
+    integer c = P::g(3);
+    integer d = P::Z;
+
+    assert property (a == 2);
+    assert property (b == 9);
+    assert property (c == 8);
+    assert property (d == 16);
+endmodule