hw/cxl: Add fixes in Post Package Repair (PPR)

Add following fixes to the commit: hw/cxl: Add support for Maintenance
command and Post Package Repair (PPR).

In cxl_perform_ppr(), remove and free the maintenance entry from QLIST
if match is found and PPR operation is performed.

Fixes: 5e5a86bab830("hw/cxl: Add support for Maintenance command and Post Package Repair (PPR)")
Signed-off-by: Shiju Jose <shiju.jose@huawei.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20260306101423.986-3-shiju.jose@huawei.com>