PCI: designware: Remove PCI_PROBE_ONLY handling

The PCIe designware host driver is not used in system configurations
requiring the PCI_PROBE_ONLY flag to be set to prevent resources
assignment, therefore the driver code handling the flag can be removed
from the kernel.

Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Pratyush Anand <pratyush.anand@gmail.com>
Acked-by: Jingoo Han Jingoo Han <jingoohan1@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Gabriele Paoloni <gabriele.paoloni@huawei.com>
Cc: Zhou Wang <wangzhou1@hisilicon.com>