pci_ep: layerscape: Add the workaround for errata A-009460

The VF_BARn_REG register's Prefetchable and Type bit fields
are overwritten by a write to VF's BAR Mask register.
workaround: Before writing to the VF_BARn_MASK_REG register,
write 0b to the PCIE_MISC_CONTROL_1_OFF register.

Signed-off-by: Xiaowei Bao <xiaowei.bao@nxp.com>
Signed-off-by: Hou Zhiqiang <Zhiqiang.Hou@nxp.com>
Reviewed-by: Priyanka Jain <priyanka.jain@nxp.com>