drm/i915: Remove warning from the rps worker

In commit 4e5c8a99 ("drm/i915: Drop i915_request.lock requirement
for intel_rps_boost()"), we decoupled the rps worker from the pm so
that we could avoid the synchronization penalty which makes the
assertion liable to run too early. Which makes warning invalid hence
removed.

Fixes: 4e5c8a99

 ("drm/i915: Drop i915_request.lock requirement for intel_rps_boost()")

Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Tejas Upadhyay <tejaskumarx.surendrakumar.upadhyay@intel.com>
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210914090412.1393498-1-tejaskumarx.surendrakumar.upadhyay@intel.com