MAINTAINERS: INTEL DRM DRIVERS list (intel-gfx) is subscribers-only

Mark it so.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
diff --git a/MAINTAINERS b/MAINTAINERS
index a92c994..86f9bb6 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -2080,7 +2080,7 @@
 
 INTEL DRM DRIVERS (excluding Poulsbo, Moorestown and derivative chipsets)
 M:	Chris Wilson <chris@chris-wilson.co.uk>
-L:	intel-gfx@lists.freedesktop.org
+L:	intel-gfx@lists.freedesktop.org (subscribers-only)
 L:	dri-devel@lists.freedesktop.org
 T:	git git://git.kernel.org/pub/scm/linux/kernel/git/ickle/drm-intel.git
 S:	Supported