tests: Add tests for DRAM low power modes

This patch adds two regression tests that execute the script in the
configs dir for triggering low power mode transitions. A separate
test is required for each page policy because for close-adaptive
page policy the DRAM goes into the Precharge Power-down mode while
for open-adaptive page policy it goes into the Activate Power-down
mode.

Change-Id: Iad61af23f132db046f2857cc3ef64b2bf42cf5e4
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/5726
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

stats: Get all stats updated to reflect current behaviour

Line everything up again.

tests, ruby: Move rubytests from ALPHA (linux) to NULL (none)

This patch avoids compiling ALPHA six times as part of running
'util/regress', and instead relis on NULL with different protocols to
run the rubytest. All we need is the memory system, so there is really
no need to compile the ISA over and over again.

The one downside is the removal of running 'hello' for the variuos
ALPHA and protocol combinations, but if this is a concern we should
rather beef up the synthetic tests for the variuos protocols.

stats: update references

stats: Add power stats to test references

Change-Id: Ic827213134b199446822f128b81d4a480e777fee

stats: update for snoop filter tweak

stats: update stats for thermals, indirect BP

stats: Update stats to reflect changes to cache and crossbar

stats: update stats to after GPU checkin

stats: bump stats to reflect ruby tester changes

stats: updates due to recent chagnesets

stats: Update stats to match cache changes

stats: slight changes to MOESI_CMP_token.

Due slight change to latency for the reissue table.

stats: updates due to recent changesets including d0934b57735a

stats: updates due to recent changes.

stats: Bump for MessageBuffer, cache latency changes

stats: Reflect current behaviour

Not sure what went wrong in the pushing of the Ruby patches, but
somehow these regressions are not updated.

stats: update stale config.ini files, eio and few other stats.

stats: Update stats for cache, crossbar and DRAM changes

This update includes the changes to whole-line writes, the refinement
of Read to ReadClean and ReadShared, the introduction of CleanEvict
for snoop-filter tracking, and updates to the DRAM command scheduler
for bank-group-aware scheduling.

Needless to say, almost every regression is affected.

stats: changes to due to recent set of patches

stats: Bump stats for decoder, TLB, prefetcher and DRAM changes

Changes due to speculative execution of an unaligned PC, introduction
of TLB stats, changes and re-work of the prefetcher, and the
introduction of rank-wise refresh in the DRAM controller.

stats: updates due to changes to ruby

stats: Update stats for CPU and cache changes

This patch updates the stats to reflect the fixes and changes to the
CPU (mainly the o3), and the caches.

stats: updates due to recent ruby and x86 changes
Also updates many out of date config files.

stats: changes due to o3 cpu and ruby message buffer patches

stats: update stats for cache occupancy and clock domain changes