PCI: rockchip-ep: Mark RK3399 as intx_capable

RK3399 can raise INTx interrupts, as can be seen by
rockchip_pcie_ep_send_intx_irq().

This is also in line with the register description of
PCIE_CLIENT_LEGACY_INT_CTRL, section "17.6.3 PCIe Client Detail Register
Description" of the RK3399 TRM.

Thus, mark RK3399 as intx_capable.

Signed-off-by: Niklas Cassel <cassel@kernel.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://patch.msgid.link/20250416142749.336298-2-cassel@kernel.org

Author: floatious

drivers/pci/controller/pcie-rockchip-ep.c

@@ -694,6 +694,7 @@ static const struct pci_epc_features rockchip_pcie_epc_features = {
 	.linkup_notifier = true,
 	.msi_capable = true,
 	.msix_capable = false,
+	.intx_capable = true,
 	.align = ROCKCHIP_PCIE_AT_SIZE_ALIGN,
 };