If there is no port multiplier, PortMultiplierPort should be converted
to 0 to follow AHCI spec.
The same logic already applied in AtaAtapiPassThruDxe driver.
Signed-off-by: Neo Hsueh <Hong-Chih.Hsueh@amd.com>
Acked-by: Abner Chang <abner.chang@amd.com>
Reviewed-by: Hao A Wu <hao.a.wu@intel.com>