PCI: of: Add of_pci_preserve_config() for per-host bridge support
Add of_pci_preserve_config() to look for the "linux,pci-probe-only"
property under a specified node. If it's not found there, look under
"of_chosen" in addition.
If the caller didn't specify a node, look under "of_chosen".
With a future patch, this will support "linux,pci-probe-only" on a per host
bridge basis based on the presence of the property in the respective PCI
host bridge DT node.
Implement of_pci_check_probe_only() using of_pci_preserve_config().
Link: https://lore.kernel.org/r/20240508174138.3630283-3-vidyas@nvidia.com
Signed-off-by: Vidya Sagar <vidyas@nvidia.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>