cxgb4: collect MC memory dump

Use meminfo to get base address and size of MC memory.  Also use same
meminfo for EDC memory dumps.

Signed-off-by: Rahul Lakkireddy <rahul.lakkireddy@chelsio.com>
Signed-off-by: Ganesh Goudar <ganeshgr@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>