When checking the response verb, the valid bit should be masked out,
since its value flips depending on what Response Register
(RR0 /RR1) it's been read from.

Fixes: 321eecb0 ("bus: fsl-mc: dpio: add QBMan portal APIs for DPAA2")
Signed-off-by: Horia Geantă <horia.geanta@nxp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>