genirq: Provide generic_handle_domain_irq_safe().

Provide generic_handle_domain_irq_safe() which can used from any context.
This similar to commit
   509853f9

 ("genirq: Provide generic_handle_irq_safe()")

but this time for the irq-domains interface. It has been reported for
the amd-pinctrl driver via bugzilla
   https://bugzilla.kernel.org/show_bug.cgi?id=215954

I looked around and added a few users so it is not just one user API :)
Instead of generic_handle_irq(irq_find_mapping)) one can use
generic_handle_domain_irq().

The problem with generic_handle_domain_irq() is that with `threadirqs'
it will trigger "WARN_ON_ONCE(!in_hardirq())". That interrupt handler
can't be marked non-threaded because it is a shared handler (it is
marked as such and I can't tell the interrupt can be really shared on
the system).
Ignoring the just mentioned warning, on PREEMPT_RT the threaded handler
is invoked with enabled interrupts leading other problems.

Do we do this?

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Link: https://lore.kernel.org/r/YnkfWFzvusFFktSt@linutronix.de