drm/i915/perf: don't forget noa wait after oa config

I'm observing incoherence metric values, changing from run to run.

It appears the patches introducing noa wait & reconfiguration from
command stream switched places in the series multiple times during the
review. This lead to the dependency of one onto the order to go
missing...

Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Fixes: 15d0ace1 ("drm/i915/perf: execute OA configuration from command stream")
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20191113154639.27144-1-lionel.g.landwerlin@intel.com