fsl_pci: Add support for FSL PCIe controllers v2.x

FSL PCIe controller v2.1:
	- New MSI inbound window
	- Same Inbound windows address as PCIe controller v1.x

Added new pit_t member(pmit) to struct ccsr_pci for MSI inbound window

FSL PCIe controller v2.2 and v2.3:
	- Different addresses for PCIe inbound window 3,2,1
	- Exposed PCIe inbound window 0
	- New PCIe interrupt status register

Added new Interrupt Status register to struct ccsr_pci & updated pit_t array
size to reflect the 4 inbound windows.

To maintain backward compatiblilty, on V2.2 or greater controllers we
start with inbound window 1 and leave inbound 0 with its default value
(which maps to CCSRBAR).

Signed-off-by: Prabhakar Kushwaha <prabhakar@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>