drm/i915: More renaming of rings to engines

This time using only sed and a few by hand.

v2: Rename also intel_ring_id and intel_ring_initialized.
v3: Fixed typo in intel_ring_initialized.

Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/1458126040-33105-1-git-send-email-tvrtko.ursulin@linux.intel.com
diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c
index 63ed77f..0f61ae0 100644
--- a/drivers/gpu/drm/i915/i915_irq.c
+++ b/drivers/gpu/drm/i915/i915_irq.c
@@ -996,7 +996,7 @@
 
 static void notify_ring(struct intel_engine_cs *engine)
 {
-	if (!intel_ring_initialized(engine))
+	if (!intel_engine_initialized(engine))
 		return;
 
 	trace_i915_gem_request_notify(engine);