hw/mem/cxl_type3: Add DC extent list representative and get DC extent list mailbox...

hw/mem/cxl_type3: Add DC extent list representative and get DC extent list mailbox support

Add dynamic capacity extent list representative to the definition of
CXLType3Dev and implement get DC extent list mailbox command per
CXL.spec.3.1:.8.2.9.9.9.2.

Tested-by: Svetly Todorov <svetly.todorov@memverge.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Fan Ni <fan.ni@samsung.com>
Message-Id: <20240523174651.1089554-10-nifan.cxl@gmail.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>