configs: rockchip: rock5b-rk3588: Enable CONFIG_PCI_INIT_R

Enable CONFIG_PCI_INIT_R for rock5b pci enumeration during boot in order
to autodetect the PCI ethernet NIC during the boot process.

Signed-off-by: Christopher Obbard <chris.obbard@collabora.com>
Reviewed-by: Kever Yang <kever.yang@rock-chips.com>