Remove TCL_TRACE_READS for Tcl_TraceVar(net-type)

Patch by: michaelortmann

The concept idea was:
    - Write trace to give that warning and update the C variable.
    - Read trace to return a string to Tcl whenever the variable is read instead of the internal number.

However, existing scripts might rely on this being a number from Tcl's point of view. This is fine until we decide to change that.

src/mod/server.mod/server.c

@@ -2096,7 +2096,7 @@ static char *server_close()
                  TCL_TRACE_READS | TCL_TRACE_WRITES | TCL_TRACE_UNSETS,
                  traced_serveraddress, NULL);
   Tcl_UntraceVar(interp, "net-type",
-                 TCL_TRACE_READS | TCL_TRACE_WRITES | TCL_TRACE_UNSETS,
+                 TCL_TRACE_WRITES | TCL_TRACE_UNSETS,
                  traced_nettype, NULL);
   Tcl_UntraceVar(interp, "nick-len",
                  TCL_TRACE_READS | TCL_TRACE_WRITES | TCL_TRACE_UNSETS,
@@ -2269,7 +2269,7 @@ char *server_start(Function *global_funcs)
                TCL_TRACE_READS | TCL_TRACE_WRITES | TCL_TRACE_UNSETS,
                traced_serveraddress, NULL);
   Tcl_TraceVar(interp, "net-type",
-               TCL_TRACE_READS | TCL_TRACE_WRITES | TCL_TRACE_UNSETS,
+               TCL_TRACE_WRITES | TCL_TRACE_UNSETS,
                traced_nettype, NULL);
   Tcl_TraceVar(interp, "nick-len",
                TCL_TRACE_READS | TCL_TRACE_WRITES | TCL_TRACE_UNSETS,