edit: Really fix the completion of last character

The previous commit broke completion in various places. The proper
way of handling the completion of full word is to verify whether
there are more than one possible match at that point.

src/utils/edit.c

@@ -377,7 +377,7 @@ static void complete(int list)
 	}
 
 	len = max_common_length(c);
-	if (len < plen) {
+	if (len <= plen && count > 1) {
 		if (list) {
 			edit_clear_line();
 			printf("\r");