FROMLIST: genirq: Allow an interrupt to be marked as 'raw'

Some interrupts (such as the rescheduling IPI) rely on not going through
the irq_enter()/irq_exit() calls. To distinguish such interrupts, add
a new IRQ flag that allows the low-level handling code to sidestep the
enter()/exit() calls.

Only the architecture code is expected to use this. It will do the wrong
thing on normal interrupts. Note that this is a band-aid until we can
move to some more correct infrastructure (such as kernel/entry/common.c).

Bug: 191808738
Link: https://lore.kernel.org/lkml/20201124141449.572446-3-maz@kernel.org/


Change-Id: I0609a8b689219ba9e769c8b9f7fcf1e77a0ff1ca
Signed-off-by: Marc Zyngier <maz@kernel.org>
[minor port to 5.10]
Signed-off-by: Stephen Dickey <dickey@codeaurora.org>