tests: Shorten line in table-features test.

By inserting "dnl" a few places in this 1000+ character line, we bring
the physical line length down (making "git format-patch" willing to put
it into a patch) but m4 will still paste it together into a single line.

Signed-off-by: Ben Pfaff <blp@nicira.com>
Acked-by: Joe Stringer <joestringer@nicira.com>

tests/ofproto.at

@@ -1529,7 +1529,9 @@ head_table () {
       instructions: meter,apply_actions,clear_actions,write_actions,write_metadata,goto_table
       Write-Actions and Apply-Actions features:
         actions: output group set_field strip_vlan push_vlan mod_nw_ttl dec_ttl set_mpls_ttl dec_mpls_ttl push_mpls pop_mpls set_queue
-        supported on Set-Field: tun_id tun_src tun_dst tun_flags tun_gbp_id tun_gbp_flags tun_metadata0 tun_metadata1 tun_metadata2 tun_metadata3 tun_metadata4 tun_metadata5 tun_metadata6 tun_metadata7 tun_metadata8 tun_metadata9 tun_metadata10 tun_metadata11 tun_metadata12 tun_metadata13 tun_metadata14 tun_metadata15 tun_metadata16 tun_metadata17 tun_metadata18 tun_metadata19 tun_metadata20 tun_metadata21 tun_metadata22 tun_metadata23 tun_metadata24 tun_metadata25 tun_metadata26 tun_metadata27 tun_metadata28 tun_metadata29 tun_metadata30 tun_metadata31 tun_metadata32 tun_metadata33 tun_metadata34 tun_metadata35 tun_metadata36 tun_metadata37 tun_metadata38 tun_metadata39 tun_metadata40 tun_metadata41 tun_metadata42 tun_metadata43 tun_metadata44 tun_metadata45 tun_metadata46 tun_metadata47 tun_metadata48 tun_metadata49 tun_metadata50 tun_metadata51 tun_metadata52 tun_metadata53 tun_metadata54 tun_metadata55 tun_metadata56 tun_metadata57 tun_metadata58 tun_metadata59 tun_metadata60 tun_metadata61 tun_metadata62 tun_metadata63 metadata in_port in_port_oxm pkt_mark reg0 reg1 reg2 reg3 reg4 reg5 reg6 reg7 xreg0 xreg1 xreg2 xreg3 eth_src eth_dst vlan_tci vlan_vid vlan_pcp mpls_label mpls_tc ip_src ip_dst ipv6_src ipv6_dst ipv6_label nw_tos ip_dscp nw_ecn nw_ttl arp_op arp_spa arp_tpa arp_sha arp_tha tcp_src tcp_dst udp_src udp_dst sctp_src sctp_dst nd_target nd_sll nd_tll
+        supported on Set-Field: tun_id tun_src tun_dst tun_flags tun_gbp_id tun_gbp_flags tun_metadata0 dnl
+tun_metadata1 tun_metadata2 tun_metadata3 tun_metadata4 tun_metadata5 tun_metadata6 tun_metadata7 tun_metadata8 tun_metadata9 tun_metadata10 tun_metadata11 tun_metadata12 tun_metadata13 tun_metadata14 tun_metadata15 tun_metadata16 tun_metadata17 tun_metadata18 tun_metadata19 tun_metadata20 tun_metadata21 tun_metadata22 tun_metadata23 tun_metadata24 tun_metadata25 tun_metadata26 tun_metadata27 tun_metadata28 tun_metadata29 tun_metadata30 tun_metadata31 tun_metadata32 tun_metadata33 tun_metadata34 tun_metadata35 tun_metadata36 tun_metadata37 tun_metadata38 tun_metadata39 tun_metadata40 tun_metadata41 tun_metadata42 tun_metadata43 tun_metadata44 tun_metadata45 tun_metadata46 tun_metadata47 tun_metadata48 tun_metadata49 tun_metadata50 tun_metadata51 tun_metadata52 tun_metadata53 tun_metadata54 tun_metadata55 tun_metadata56 tun_metadata57 tun_metadata58 tun_metadata59 tun_metadata60 tun_metadata61 tun_metadata62 tun_metadata63 dnl
+metadata in_port in_port_oxm pkt_mark reg0 reg1 reg2 reg3 reg4 reg5 reg6 reg7 xreg0 xreg1 xreg2 xreg3 eth_src eth_dst vlan_tci vlan_vid vlan_pcp mpls_label mpls_tc ip_src ip_dst ipv6_src ipv6_dst ipv6_label nw_tos ip_dscp nw_ecn nw_ttl arp_op arp_spa arp_tpa arp_sha arp_tha tcp_src tcp_dst udp_src udp_dst sctp_src sctp_dst nd_target nd_sll nd_tll
     matching:
       dp_hash: arbitrary mask
       recirc_id: exact match or wildcard