iommu/hyper-v: Use helper instead of directly accessing affinity

Recent changes to solve inconsistencies in handling IRQ masks #ifdef
out the affinity field in irq_common_data for non-SMP configurations.
The current code in hyperv_irq_remapping_alloc() gets a compiler error
in that case.

Fix this by using the new irq_data_update_affinity() helper, which
handles the non-SMP case correctly.

Signed-off-by: Michael Kelley <mikelley@microsoft.com>
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Fixes: aa081358 ("genirq: Provide an IRQ affinity mask in non-SMP configs")
Link: https://lore.kernel.org/r/1658796820-2261-1-git-send-email-mikelley@microsoft.com