irqdomain: Drop of_node_to_fwnode()

irqdomain: Drop of_node_to_fwnode()

All uses of of_node_to_fwnode() in non-irqdomain code were changed to
"officially" defined of_fwnode_handle(). Therefore, the former can be
dropped along with the last uses in the irqdomain code.

Due to merge logistics the inline cannot be dropped immediately. Move it to
a deprecated section, which will be removed during the merge window.

[ tglx: Handle merge logistics ]

Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/20250319092951.37667-12-jirislaby@kernel.org