tshark: Correct documentation about name resolution.

The tshark help and documentation has been incorrect for at least
eight years, claiming that by default all name resolutions are
performed. Fixes #11762

doc/tshark.pod

@@ -624,8 +624,11 @@ names); the B<-N> option might override this one.
 Turn on name resolving only for particular types of addresses and port
 numbers, with name resolving for other types of addresses and port
 numbers turned off.  This option overrides B<-n> if both B<-N> and B<-n>
-are present.  If both B<-N> and B<-n> options are not present, all name
-resolutions are turned on.
+are present.  This option and B<-n> override the options from the preferences,
+including preferences set via the B<-o> option.  If both B<-N> and B<-n> options
+are not present, the values from the preferences are used, which default to
+B<d>, B<m>, and B<N> turned on and the other options turned off. (NB, B<N> does
+not actually do anything without B<n> enabled as well.)
 
 The argument is a string that may contain the letters:
 
@@ -636,7 +639,7 @@ B<m> to enable MAC address resolution
 B<n> to enable network address resolution
 
 B<N> to enable using external resolvers (e.g., DNS) for network address
-resolution
+resolution; no effect without B<n> also enabled
 
 B<t> to enable transport-layer port number resolution
 

docbook/wsug_src/tshark-h.txt

@@ -51,7 +51,8 @@ Processing:
   -Y <display filter>, --display-filter <display filter>
                            packet displaY filter in Wireshark display filter
                            syntax
-  -n                       disable all name resolutions (def: all enabled)
+  -n                       disable all name resolutions (def: "mNd" enabled, or
+                           as set in preferences)
   -N <name resolve flags>  enable specific name resolution(s): "mnNtdv"
   -d <layer_type>==<selector>,<decode_as_protocol> ...
                            "Decode As", see the man page for details

tshark.c

@@ -400,7 +400,8 @@ print_usage(FILE *output)
   fprintf(output, "  -Y <display filter>, --display-filter <display filter>\n");
   fprintf(output, "                           packet displaY filter in Wireshark display filter\n");
   fprintf(output, "                           syntax\n");
-  fprintf(output, "  -n                       disable all name resolutions (def: all enabled)\n");
+  fprintf(output, "  -n                       disable all name resolutions (def: \"mNd\" enabled, or\n");
+  fprintf(output, "                           as set in preferences)\n");
   fprintf(output, "  -N <name resolve flags>  enable specific name resolution(s): \"mnNtdv\"\n");
   fprintf(output, "  -d %s ...\n", DECODE_AS_ARG_TEMPLATE);
   fprintf(output, "                           \"Decode As\", see the man page for details\n");