systemc: Print an Info when setting a tracefile's time unit.

This matches Accellera's output for the tests.

Change-Id: Ie67fd673a980b8ca2fdcd8f357ff7993a9091221
Reviewed-on: https://gem5-review.googlesource.com/c/12972
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Gabe Black <gabeblack@google.com>
1 file changed