igb: Enable RSS for Intel I211 Ethernet Controller

igb: Enable RSS for Intel I211 Ethernet Controller

The Intel I211 Ethernet Controller supports 2 Receive Side Scaling (RSS)
queues. It should not be excluded from having this feature enabled.

Via commit c883de9fd787 ("igb: rename igb define to be more generic")
E1000_MRQC_ENABLE_RSS_4Q was renamed to E1000_MRQC_ENABLE_RSS_MQ to
indicate that this is a generic bit flag to enable queues and not
a flag that is specific to devices that support 4 queues

The bit flag enables 2, 4 or 8 queues appropriately depending on the part.

Tested with a multicore CPU and frames were then distributed as expected.

This issue appears to have been introduced because of confusion caused
by the prior name.

Signed-off-by: Nick Lowe <nick.lowe@gmail.com>
Tested-by: David Switzer <david.switzer@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>