ARM: dts: msm: Add MSM PCIe bus driver device nodes for sa6155

Add MSM PCIe bus driver device nodes in main and pinctrl
devicetree for sa6155 to enable communication between sa6155
and external peripherals connected via PCIe.

Change-Id: I47018006d5c61528b3d3539dbf5eddc24b7df7b0
Signed-off-by: Rama Krishna Phani A <rphani@codeaurora.org>