lantiq: Fix PCIe bus when PCI is also enabled.

The PCIe bus seems to require a hack/workaround when PCI is enabled as
well. Unfortunately this is guarded by an CONFIG_IFX_PCI ifdef, which is
only defined in lantiq's BSP code. The config symbol for the upstream
lantiq PCI driver is CONFIG_PCI_LANTIQ.

Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>

SVN-Revision: 45717