dev: terminal: run pollevent in terminal eventq

Change-Id: Idefda0ca1cd71d3e790d470458fa1cd370393c4a
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/67532
Reviewed-by: Gabe Black <gabe.black@gmail.com>
Maintainer: Gabe Black <gabe.black@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>

src/dev/serial/terminal.cc

@@ -87,6 +87,10 @@ Terminal::ListenEvent::ListenEvent(Terminal *t, int fd, int e)
 void
 Terminal::ListenEvent::process(int revent)
 {
+    // As a consequence of being called from the PollQueue, we might
+    // have been called from a different thread. Migrate to "our"
+    // thread.
+    EventQueue::ScopedMigration migrate(term->eventQueue());
     term->accept();
 }