drm: use noop_llseek

The drm device drivers currently allow seeking on the
character device but never care about the actual
file position.

When we change the default llseek operation to be
no_llseek, calling llseek on a drm device would
return an error condition, which is an API change.

Explicitly setting noop_llseek lets us keep the
current API.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: David Airlie <airlied@linux.ie>
Cc: dri-devel@lists.freedesktop.org
diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_drv.c b/drivers/gpu/drm/vmwgfx/vmwgfx_drv.c
index 72ec2e2..d237190 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_drv.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_drv.c
@@ -745,6 +745,7 @@
 #if defined(CONFIG_COMPAT)
 		 .compat_ioctl = drm_compat_ioctl,
 #endif
+		 .llseek = noop_llseek,
 		 },
 	.pci_driver = {
 		       .name = VMWGFX_DRIVER_NAME,