hw/cxl: mailbox-utils: 0x5603 - FMAPI Get DC Region Extent Lists

hw/cxl: mailbox-utils: 0x5603 - FMAPI Get DC Region Extent Lists

FM DCD Management command 0x5603 implemented per CXL r3.2 Spec Section 7.6.7.6.4
Very similar to previously implemented command 0x4801.

Reviewed-by: Fan Ni <fan.ni@samsung.com>
Signed-off-by: Anisa Su <anisa.su@samsung.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Message-Id: <20250714174509.1984430-9-Jonathan.Cameron@huawei.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>