ixgbe: Add support for macvlan offload RSS on X550 and clean-up pool handling

In order for RSS to work on the macvlan pools of the X550 we need to
populate the MRQC, RETA, and RSS key values for each pool. This patch makes
it so that we now take care of that.

In addition I have dropped the macvlan specific configuration of psrtype
since it is redundant with the code that already exists for configuring
this value.

Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>