systemc: Fix gcc13 systemC compilation error (#520)

issue: https://github.com/gem5/gem5/issues/472

src/systemc/ext/core/sc_port.hh

@@ -114,6 +114,10 @@ class sc_port_base : public sc_object
     virtual sc_port_policy _portPolicy() const = 0;
 };
 
+// The overloaded virtual is intended in SystemC, so we'll disable the warning.
+// Please check section 9.3 of SystemC 2.3.1 release note for more details.
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Woverloaded-virtual"
 template <class IF>
 class sc_port_b : public sc_port_base
 {
@@ -244,6 +248,7 @@ class sc_port_b : public sc_port_base
     sc_port_b(const sc_port_b<IF> &) {}
     sc_port_b<IF> &operator = (const sc_port_b<IF> &) { return *this; }
 };
+#pragma GCC diagnostic pop
 
 template <class IF, int N=1, sc_port_policy P=SC_ONE_OR_MORE_BOUND>
 class sc_port : public sc_port_b<IF>