check_icmp does not have the -p argument in the help

Fix for issue #158

`-n` was documented, `-p` was not. They both are used to
specify the number of packets.

NEWS

@@ -5,6 +5,7 @@ This file documents the major additions and syntax changes between releases.
 	check_http: -e breaks -f
 	check_mrtg: Add state to status output
 	check_ping: ping runs 30 times when host is down
+	check_icmp: does not have the -p argument in the help
 
 
 2.1.4 2016-11-17

plugins-root/check_icmp.c

@@ -1381,6 +1381,9 @@ print_help(void)
   printf (" %s\n", "-n");
   printf ("    %s", _("number of packets to send (currently "));
   printf ("%u)\n",packets);
+  printf (" %s\n", "-p");
+  printf ("    %s", _("number of packets to send (currently "));
+  printf ("%u)\n",packets);
   printf (" %s\n", "-i");
   printf ("    %s", _("max packet interval (currently "));
   printf ("%0.3fms)\n",(float)pkt_interval / 1000);