Revert "ethtool: Add n-tuple string length to drvinfo and return it"

Revert "ethtool: Add n-tuple string length to drvinfo and return it"

This reverts commit 235467c122a56b8db78067bb1f4b7ba3cf174db3.

As Jeff points out we can't break the user visible interface
like this, we need to add this into the reserved[] thing.

Signed-off-by: David S. Miller <davem@davemloft.net>