smtp layer: reset app layer after STARTTLS

This patch updates SMTP layer to ask for a reset of application
layer when a successful STARTTLS command is seen. A full reset is
asked to allow the application layer to skip server answer and
continue to proceed the data.

src/app-layer-smtp.c

@@ -846,11 +846,8 @@ static int SMTPProcessReply(SMTPState *state, Flow *f,
         /* reply but not a command we have stored, fall through */
     } else if (state->cmds[state->cmds_idx] == SMTP_COMMAND_STARTTLS) {
         if (reply_code == SMTP_REPLY_220) {
-            /* we are entering STARRTTLS data mode */
-            state->parser_state |= SMTP_PARSER_STATE_COMMAND_DATA_MODE;
-            AppLayerParserStateSetFlag(pstate,
-                                             APP_LAYER_PARSER_NO_INSPECTION |
-                                             APP_LAYER_PARSER_NO_REASSEMBLY);
+            /* we reset the alproto */
+            AppLayerAskReset(f, 1);
         } else {
             /* decoder event */
             SMTPSetEvent(state, SMTP_DECODER_EVENT_TLS_REJECTED);