systemc: Implement sc_event_queue.

Change-Id: I58fd72b8c64ee82eb478d810f7114bab7a31cbfa
Reviewed-on: https://gem5-review.googlesource.com/c/13184
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Gabe Black <gabeblack@google.com>
2 files changed