linux-imx

iommu/vt-d: Delete unnecessary check in domain_context_mapping_one()

Variable did_old is unsigned so checking whether it is
greater or equal to zero is not necessary.

Signed-off-by: Christos Gkekas <chris.gekas@gmail.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>