Approach copied from gen_pcie_root_port.c
Previously the link defaulted to a maximum of 2.5GT/s and 1x. Enable setting
it's maximum values. The actual value after 'training' will depend on the
downstream device configuration.
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Message-Id: <20240916173518.1843023-2-Jonathan.Cameron@huawei.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Fan Ni <fan.ni@samsung.com>