Enable CPX mode for MI300X (#1259)

* graph: enable cpx mode for MI300X

* graph: tune limits for cpx and cleanup

[ROCm/rccl commit: 6f331b0d43]

projects/rccl/src/graph/xml.h

@@ -17,7 +17,7 @@
 // A few constraints to make the implementation easy
 #define MAX_STR_LEN 255
 #define MAX_ATTR_COUNT 16
-#define MAX_SUBS 32
+#define MAX_SUBS 64	//Changed the value from 32 to 64 for CPX mode
 #define MAX_NODES 1024
 
 #define NODE_TYPE_NONE 0