PCI: dw-rockchip: Don't wait for link since we can detect Link Up

The Root Complex specific device tree binding for pcie-dw-rockchip has the
'sys' interrupt marked as required.

The driver requests the 'sys' IRQ unconditionally, and errors out if not
provided.

Thus, we can unconditionally set 'use_linkup_irq', so dw_pcie_host_init()
doesn't wait for the link to come up.

This will skip the wait for link up (since the bus will be enumerated once
the link up IRQ is triggered), which reduces the bootup time.

Link: https://lore.kernel.org/r/20250113-rockchip-no-wait-v1-1-25417f37b92f@kernel.org


Signed-off-by: Niklas Cassel <cassel@kernel.org>
[bhelgaas: commit log]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>