pci: Convert child classes of TYPE_PCIE_ROOT_PORT to 3-phase reset

pci: Convert child classes of TYPE_PCIE_ROOT_PORT to 3-phase reset

Convert the TYPE_CXL_ROOT_PORT and TYPE_PNV_PHB_ROOT_PORT classes to
3-phase reset, so they don't need to use the deprecated
device_class_set_parent_reset() function any more.

We have to do both in the same commit, because they keep the
parent_reset field in their common parent class's class struct.

Note that pnv_phb_root_port_class_init() was pointlessly setting
dc->reset twice, once by calling device_class_set_parent_reset()
and once directly.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Tested-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-id: 20221125115240.3005559-5-peter.maydell@linaro.org