Match Marvell Armada38X PCI compatible with Linux

[mkm_semihalf.com]

Summary

In Linux FDT pcie does not have compatible string.
Configuration of windows in mv_common was based on fdt compatible.
Now pcie windows are configured by their parent: pcie_controller.
Processing is moved to fdt_win_process_child. fdt_win_process now
only walk through the tree. SOC_NODE_PCI is position of pcie function in
soc_node_spec array.

PCIe probe cannot use ofw_bus_search_compatible, because it needs to
check also device type and parents compatible.

[manu]

Same comment as in D14751 :

I don't understand why we need this dts since we have it in sys/gnu/dts.
I should be easier to include the gnu one from a FreeBSD one that patches node if we need some difference.

[mw]

HI Manu,

Please check my answer in answer in https://reviews.freebsd.org/D14751. DTS part is temporary until completer removal.

[manu]

OK for DTS part