Re-enable EDNS if an EDNS flag gets set to 1 by +ednsflags

This is consistent with +dnssec and +nsid which only re-enable
EDNS if do is set to 1 or nsid is requested.

bin/dig/dig.c

@@ -1797,6 +1797,10 @@ plus_option(char *option, bool is_batchfile, bool *need_clone,
 							     "ednsflags");
 							goto exit_or_usage;
 						}
+						if (lookup->edns == -1) {
+							lookup->edns =
+								DEFAULT_EDNS_VERSION;
+						}
 						lookup->ednsflags = num;
 						break;
 					case 'n':

bin/tools/mdig.c

@@ -1354,6 +1354,9 @@ plus_option(char *option, struct query *query, bool global) {
 							"ednsflags");
 						CHECK("parse_xint(ednsflags)",
 						      result);
+						if (query->edns == -1) {
+							query->edns = 1;
+						}
 						query->ednsflags = num;
 						break;
 					case 'o':