iommu/vt-d: Avoid GFP_ATOMIC where it is not needed

There is no reason to use GFP_ATOMIC in a 'suspend' function.
Use GFP_KERNEL instead to give more opportunities to allocate the
requested memory.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: https://lore.kernel.org/r/20201030182630.5154-1-christophe.jaillet@wanadoo.fr


Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/20201201013149.2466272-2-baolu.lu@linux.intel.com


Signed-off-by: Will Deacon <will@kernel.org>