const: mark struct vm_struct_operations

* mark struct vm_area_struct::vm_ops as const
* mark vm_ops in AGP code

But leave TTM code alone, something is fishy there with global vm_ops
being used.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/media/video/stk-webcam.c b/drivers/media/video/stk-webcam.c
index 0b996ea..6b41865 100644
--- a/drivers/media/video/stk-webcam.c
+++ b/drivers/media/video/stk-webcam.c
@@ -790,7 +790,7 @@
 	if (sbuf->mapcount == 0)
 		sbuf->v4lbuf.flags &= ~V4L2_BUF_FLAG_MAPPED;
 }
-static struct vm_operations_struct stk_v4l_vm_ops = {
+static const struct vm_operations_struct stk_v4l_vm_ops = {
 	.open = stk_v4l_vm_open,
 	.close = stk_v4l_vm_close
 };