Enable CPX mode for MI300X (#1259)

* graph: enable cpx mode for MI300X

* graph: tune limits for cpx and cleanup

src/graph/topo.cc

@@ -295,7 +295,7 @@ static ncclResult_t ncclTopoPrintRec(struct ncclTopoNode* node, struct ncclTopoN
 
 ncclResult_t ncclTopoPrint(struct ncclTopoSystem* s) {
   INFO(NCCL_GRAPH, "=== System : maxBw %2.1f totalBw %2.1f ===", s->maxBw, s->totalBw);
-  char line[1024];
+  char line[2048];
   for (int n=0; n<s->nodes[CPU].count; n++) NCCLCHECK(ncclTopoPrintRec(s->nodes[CPU].nodes+n, NULL, line, 0));
   INFO(NCCL_GRAPH, "==========================================");
   NCCLCHECK(ncclTopoPrintPaths(s));