drm/nouveau/disp,pm: constify nvkm_object_func structures

These nvkm_object_func structures are never modified.  All other
nvkm_object_func structures are declared as const.

Done with the help of Coccinelle.
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drivers/gpu/drm/nouveau/nvkm/engine/disp/rootnv04.c

@@ -109,7 +109,7 @@ nv04_disp_mthd(struct nvkm_object *object, u32 mthd, void *data, u32 size)
 	return -EINVAL;
 }
 
-static struct nvkm_object_func
+static const struct nvkm_object_func
 nv04_disp_root = {
 	.mthd = nv04_disp_mthd,
 	.ntfy = nvkm_disp_ntfy,

drivers/gpu/drm/nouveau/nvkm/engine/pm/base.c

@@ -633,7 +633,7 @@ nvkm_perfmon_dtor(struct nvkm_object *object)
 	return perfmon;
 }
 
-static struct nvkm_object_func
+static const struct nvkm_object_func
 nvkm_perfmon = {
 	.dtor = nvkm_perfmon_dtor,
 	.mthd = nvkm_perfmon_mthd,