config, arm: Add a high-performance in order timing model

config, arm: Add a high-performance in order timing model

The High-Performance In-order (HPI) CPU timing model is tuned to be
representative of a modern in-order ARMv8-A implementation. The HPI
core and its supporting simulation scripts, namely starter_se.py and
starter_fs.py (under /configs/example/arm/) are part of the ARM
Research Starter Kit on System Modeling. More information can be found
at: http://www.arm.com/ResearchEnablement/SystemModeling

Change-Id: I124bd06ba42d20abff09d447542b031d17eabe22
Signed-off-by: Ashkan Tousi <ashkan.tousimojarad@arm.com>
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/4201
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>