drm/tegra: Relax IOMMU usage criteria on old Tegra

drm/tegra: Relax IOMMU usage criteria on old Tegra

commit 2d9384ff91770a71bd1ff24c25952ef1187a0e9c upstream.

Older Tegra devices only allow addressing 32 bits of memory, so whether
or not the host1x is attached to an IOMMU doesn't matter. host1x IOMMU
attachment is only needed on devices that can address memory beyond the
32-bit boundary and where the host1x doesn't support the wide GATHER
opcode that allows it to access buffers at higher addresses.

Cc: <stable@vger.kernel.org> # v5.5
Signed-off-by: Thierry Reding <treding@nvidia.com>
Tested-by: Dmitry Osipenko <digetx@gmail.com>
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>