systemc: Add stubbed out versions of sc_port and sc_export.

Change-Id: I04edb5da995212f9179eeb7a97486031eea71aff
Reviewed-on: https://gem5-review.googlesource.com/10829
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Gabe Black <gabeblack@google.com>
5 files changed