genirq: Provide IRQCHIP_AFFINITY_PRE_STARTUP

stable inclusion
from linux-4.19.205
commit cab824f67d7e8f68288d615929dec02607e473ad

--------------------------------

commit 826da771 upstream.

X86 IO/APIC and MSI interrupts (when used without interrupts remapping)
require that the affinity setup on startup is done before the interrupt is
enabled for the first time as the non-remapped operation mode cannot safely
migrate enabled interrupts from arbitrary contexts. Provide a new irq chip
flag which allows affected hardware to request this.

This has to be opt-in because there have been reports in the past that some
interrupt chips cannot handle affinity setting before startup.

Fixes: 18404756 ("genirq: Expose default irq affinity mask (take 3)")
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Marc Zyngier <maz@kernel.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20210729222542.779791738@linutronix.de


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Conflicts:
  include/linux/irq.h
[yyl: adjust context]
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>