xen/arm: probe domU kernels and initrds

xen/arm: probe domU kernels and initrds

Find addresses, sizes on device tree from kernel_probe.
Find the cmdline from the bootcmdlines array.

Introduce a new boot_module_find_by_addr_and_kind function to match not
just on boot module kind, but also by address so that we can support
multiple domains.

Introduce a boot_cmdline_find_by_name function to find the right struct
cmdline based on the device tree node name of the "xen,domain"
compatible node.

Set command line for dom0 in kernel_probe for consistency.

Signed-off-by: Stefano Stabellini <stefanos@xilinx.com>
Acked-by: Julien Grall <julien.grall@arm.com>