v2 ethtool: remove support for ETHTOOL_GRXNTUPLE

v2 ethtool: remove support for ETHTOOL_GRXNTUPLE

This change is meant to remove all support for displaying an ntuple as
strings via ETHTOOL_GRXNTUPLE.  The reason for this change is due to the
fact that multiple issues have been found including:
 - Multiple buffer overruns for strings being displayed.
 - Incorrect filters displayed, cleared filters with ring of -2 are displayed
 - Setting get_rx_ntuple displays no rules if defined.
 - Endianess wrong on displayed values.
 - Hard limit of 1024 filters makes display functionality extremely limited

The only driver that had supported this interface was ixgbe.  Since it no
longer uses the interface and due to the issues mentioned above I am
submitting this patch to remove it.

v2:
Updated based on comments from Ben Hutchings
 - Left ETH_SS_NTUPLE_FILTERS in code but commented on it being deprecated
 - Removed ethtool_rx_ntuple_list and ethtool_rx_ntuple_flow_spec_container
 - Left ETHTOOL_GRXNTUPLE but commented it as deprecated

Also cleaned up set_rx_ntuple since there is no flow spec container to
maintain we can drop all the code for the alloc and free of it and just
return ops->set_rx_ntuple().
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Acked-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>