lwtunnel: change to use nla_parse_nested on new options

As the new options added in kernel, all should always use strict
parsing from the beginning with nla_parse_nested(), instead of
nla_parse_nested_deprecated().

Fixes: b0a21810 ("lwtunnel: add options setting and dumping for erspan")
Fixes: edf31cbb ("lwtunnel: add options setting and dumping for vxlan")
Fixes: 4ece4778

 ("lwtunnel: add options setting and dumping for geneve")
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Reviewed-by: Simon Horman <simon.horman@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>