dpaa2-mac: remove a comment regarding pause settings

The MC firmware takes these PAUSE/ASYM_PAUSE flags provided by the
driver, transforms them back into rx/tx pause enablement status and
applies them to hardware. We are not losing information by this
transformation, thus remove the comment.

Signed-off-by: Ioana Ciornei <ioana.ciornei@nxp.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>