Revert "drm: mark context support as a legacy subsystem"

This reverts commit 7c510133d93dd6f15ca040733ba7b2891ed61fd1.

Well looks like not enough digging was done, libdrm_nouveau before 2.4.33
used contexts,

292da616fe1f936ca78a3fa8e1b1b19883e343b6 nouveau: pull in major libdrm rewrite

got rid of them,

Reported-by: Paul Zimmerman <Paul.Zimmerman@synopsys.com>
Reported-by: Mikael Pettersson <mikpe@it.uu.se>
Signed-off-by: Dave Airlie <airlied@redhat.com>
diff --git a/include/drm/drmP.h b/include/drm/drmP.h
index 2907341..b46fb45 100644
--- a/include/drm/drmP.h
+++ b/include/drm/drmP.h
@@ -1322,10 +1322,9 @@
 extern int drm_rmctx(struct drm_device *dev, void *data,
 		     struct drm_file *file_priv);
 
-extern void drm_legacy_ctxbitmap_init(struct drm_device *dev);
-extern void drm_legacy_ctxbitmap_cleanup(struct drm_device *dev);
-extern void drm_legacy_ctxbitmap_release(struct drm_device *dev,
-					 struct drm_file *file_priv);
+extern int drm_ctxbitmap_init(struct drm_device *dev);
+extern void drm_ctxbitmap_cleanup(struct drm_device *dev);
+extern void drm_ctxbitmap_free(struct drm_device *dev, int ctx_handle);
 
 extern int drm_setsareactx(struct drm_device *dev, void *data,
 			   struct drm_file *file_priv);