enic: enable rq before updating rq descriptors

enic: enable rq before updating rq descriptors

BugLink: http://bugs.launchpad.net/bugs/1786352
[ Upstream commit e8588e268509292550634d9a35f2723a207683b2 ]

rq should be enabled before posting the buffers to rq desc. If not hw sees
stale value and casuses DMAR errors.

Signed-off-by: Govindarajulu Varadarajan <gvaradar@cisco.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>