drm/i915: Rename dev_priv->gtt to dev_priv->ggtt

Refer to Global GTT consistently as GGTT, thus rename dev_priv->gtt
to dev_priv->ggtt and struct i915_gtt to struct i915_ggtt.

Fix a couple of whitespace problems while at it.

v2:
- Fix a typo in commit message.

Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c
index ccdca2c..e0ba3e3 100644
--- a/drivers/gpu/drm/i915/i915_debugfs.c
+++ b/drivers/gpu/drm/i915/i915_debugfs.c
@@ -203,7 +203,7 @@
 	struct list_head *head;
 	struct drm_device *dev = node->minor->dev;
 	struct drm_i915_private *dev_priv = dev->dev_private;
-	struct i915_address_space *vm = &dev_priv->gtt.base;
+	struct i915_address_space *vm = &dev_priv->ggtt.base;
 	struct i915_vma *vma;
 	u64 total_obj_size, total_gtt_size;
 	int count, ret;
@@ -433,7 +433,7 @@
 	u32 count, mappable_count, purgeable_count;
 	u64 size, mappable_size, purgeable_size;
 	struct drm_i915_gem_object *obj;
-	struct i915_address_space *vm = &dev_priv->gtt.base;
+	struct i915_address_space *vm = &dev_priv->ggtt.base;
 	struct drm_file *file;
 	struct i915_vma *vma;
 	int ret;
@@ -492,8 +492,8 @@
 		   count, size);
 
 	seq_printf(m, "%llu [%llu] gtt total\n",
-		   dev_priv->gtt.base.total,
-		   (u64)dev_priv->gtt.mappable_end - dev_priv->gtt.base.start);
+		   dev_priv->ggtt.base.total,
+		   (u64)dev_priv->ggtt.mappable_end - dev_priv->ggtt.base.start);
 
 	seq_putc(m, '\n');
 	print_batch_pool_stats(m, dev_priv);