drm: mark drm_context support as legacy

This renames all drm-context helpers to drm_legacy_*() and moves the
internal definitions into the new drm_legacy.h header. This header is
local to DRM-core and drivers shouldn't access it.

Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
diff --git a/drivers/gpu/drm/drm_fops.c b/drivers/gpu/drm/drm_fops.c
index 955f32c..ed45ee6 100644
--- a/drivers/gpu/drm/drm_fops.c
+++ b/drivers/gpu/drm/drm_fops.c
@@ -38,6 +38,7 @@
 #include <linux/poll.h>
 #include <linux/slab.h>
 #include <linux/module.h>
+#include "drm_legacy.h"
 
 /* from BKL pushdown */
 DEFINE_MUTEX(drm_global_mutex);
@@ -416,7 +417,7 @@
 	if (dev->driver->driver_features & DRIVER_GEM)
 		drm_gem_release(dev, file_priv);
 
-	drm_ctxbitmap_flush(dev, file_priv);
+	drm_legacy_ctxbitmap_flush(dev, file_priv);
 
 	mutex_lock(&dev->master_mutex);