iris: try to set the specified tiling when importing a dmabuf

When importing a dmabuf with a specified tiling, the dmabuf user
should always try to set the tiling mode because: 1) the exporter
can set tiling AFTER exporting/importing. 2) a dmabuf could be
exported from a kernel driver other than i915, in this case the
dmabuf user and exporter need to set tiling separately.

This patch fixes a problem when running vkmark under weston with
iris on ICL, it crashed to console with the following assert. i965
doesn't have this problem as it always tries to set the specified
tiling mode.

weston: ../src/gallium/drivers/iris/iris_resource.c:990: iris_resource_from_handle: Assertion `res->bo->tiling_mode == isl_tiling_to_i915_tiling(res->surf.tiling)' failed.

Signed-off-by: James Xiong <james.xiong@intel.com>
Reviewed-by: Rafael Antognolli <rafael.antognolli@intel.com>
(cherry picked from commit b6d45e7f)