staging: fsl-mc/dpio: qbman_pull_desc_set_token() can be static

Fixes: 1628e2e4dc76 ("staging: fsl-mc/dpio: allow the driver to compile multi-arch")
Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>