drm/nouveau/nvif: split out display interface definitions

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
diff --git a/drivers/gpu/drm/nouveau/nvkm/engine/disp/cursnv50.c b/drivers/gpu/drm/nouveau/nvkm/engine/disp/cursnv50.c
index 225858e..3e9d27e 100644
--- a/drivers/gpu/drm/nouveau/nvkm/engine/disp/cursnv50.c
+++ b/drivers/gpu/drm/nouveau/nvkm/engine/disp/cursnv50.c
@@ -27,6 +27,7 @@
 #include <core/client.h>
 
 #include <nvif/class.h>
+#include <nvif/cl507a.h>
 #include <nvif/unpack.h>
 
 int