systemc: Simplify sc_time_stamp().

sc_time is now inherently based on properly scaled Ticks, so there's no
reason to try to scale it to be in picoseconds, especially since the
scaling factor may be unreliable if the timescale hasn't been fixed
yet.

Change-Id: I28baeb9792e81e1d00f6f37672df435766311864
Reviewed-on: https://gem5-review.googlesource.com/c/12974
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Gabe Black <gabeblack@google.com>
1 file changed