mem-garnet: Initialize unused Credit members

The Credit class doesn't initialize a number of its unused base class
fields.  This leads to non-determanistic traces when printing flits that
are Credits.  This patch initializes all unused fields to 0.

Change-Id: Ib73c652c71a10be57b24c0d6e1ac22eafa421e11
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/32598
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
Maintainer: Jason Lowe-Power <power.jg@gmail.com>

src/mem/ruby/network/garnet2.0/CommonTypes.hh

@@ -46,6 +46,11 @@ enum RoutingAlgorithm { TABLE_ = 0, XY_ = 1, CUSTOM_ = 2,
 
 struct RouteInfo
 {
+    RouteInfo()
+        : vnet(0), src_ni(0), src_router(0), dest_ni(0), dest_router(0),
+          hops_traversed(0)
+    {}
+
     // destination format for table-based routing
     int vnet;
     NetDest net_dest;

src/mem/ruby/network/garnet2.0/Credit.cc

@@ -37,11 +37,9 @@
 // and m_is_free_signal (whether VC is free or not)
 
 Credit::Credit(int vc, bool is_free_signal, Tick curTime)
+    : flit(0, vc, 0, RouteInfo(), 0, nullptr, 0, 0, curTime)
 {
-    m_id = 0;
-    m_vc = vc;
     m_is_free_signal = is_free_signal;
-    m_time = curTime;
     m_type = CREDIT_;
 }