liquidio: fix hang when re-binding VF host drv after running DPDK VF driver

liquidio: fix hang when re-binding VF host drv after running DPDK VF driver

BugLink: https://bugs.launchpad.net/bugs/1836117
[ Upstream commit ac13d6d8eaded15c67265eafc32f439ea3a0ac4a ]

When configuring SLI_PKTn_OUTPUT_CONTROL, VF driver was assuming that IPTR
mode was disabled by reset, which was not true.  Since DPDK driver had
set IPTR mode previously, the VF driver (which uses buf-ptr-only mode) was
not properly handling DROQ packets (i.e. it saw zero-length packets).

This represented an invalid hardware configuration which the driver could
not handle.

Signed-off-by: Rick Farrington <ricardo.farrington@cavium.com>
Signed-off-by: Felix Manlunas <felix.manlunas@cavium.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: Kleber Sacilotto de Souza <kleber.souza@canonical.com>