drm/i915: Convert dev_priv->dev backpointers to dev_priv->drm

Since drm_i915_private is now a subclass of drm_device we do not need to
chase the drm_i915_private->dev backpointer and can instead simply
access drm_i915_private->drm directly.

   text	   data	    bss	    dec	    hex	filename
1068757	   4565	    416	1073738	 10624a	drivers/gpu/drm/i915/i915.ko
1066949	   4565	    416	1071930	 105b3a	drivers/gpu/drm/i915/i915.ko

Created by the coccinelle script:
@@
struct drm_i915_private *d;
identifier i;
@@
(
- d->dev->i
+ d->drm.i
|
- d->dev
+ &d->drm
)

and for good measure the dev_priv->dev backpointer was removed entirely.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1467711623-2905-4-git-send-email-chris@chris-wilson.co.uk
diff --git a/drivers/gpu/drm/i915/i915_gem_context.c b/drivers/gpu/drm/i915/i915_gem_context.c
index b4bba8a..3c97f0e 100644
--- a/drivers/gpu/drm/i915/i915_gem_context.c
+++ b/drivers/gpu/drm/i915/i915_gem_context.c
@@ -154,7 +154,7 @@
 	struct i915_gem_context *ctx = container_of(ctx_ref, typeof(*ctx), ref);
 	int i;
 
-	lockdep_assert_held(&ctx->i915->dev->struct_mutex);
+	lockdep_assert_held(&ctx->i915->drm.struct_mutex);
 	trace_i915_context_free(ctx);
 
 	/*
@@ -465,7 +465,7 @@
 {
 	struct intel_engine_cs *engine;
 
-	lockdep_assert_held(&dev_priv->dev->struct_mutex);
+	lockdep_assert_held(&dev_priv->drm.struct_mutex);
 
 	for_each_engine(engine, dev_priv) {
 		if (engine->last_context) {
@@ -895,7 +895,7 @@
 	struct intel_engine_cs *engine = req->engine;
 
 	WARN_ON(i915.enable_execlists);
-	lockdep_assert_held(&req->i915->dev->struct_mutex);
+	lockdep_assert_held(&req->i915->drm.struct_mutex);
 
 	if (!req->ctx->engine[engine->id].state) {
 		struct i915_gem_context *to = req->ctx;