[media] dev-overlay.rst: don't ident a note

There's one note there that it is indented for no good reason.
Fix it.
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

Documentation/media/uapi/v4l/dev-overlay.rst

@@ -238,12 +238,12 @@ exceeded are undefined. [#f3]_
     :ref:`VIDIOC_S_FBUF <VIDIOC_G_FBUF>`,
     :ref:`framebuffer-flags`).
 
-    .. note::
+.. note::
 
-       This field was added in Linux 2.6.23, extending the
-       structure. However the :ref:`VIDIOC_[G|S|TRY]_FMT <VIDIOC_G_FMT>`
-       ioctls, which take a pointer to a :ref:`v4l2_format <v4l2-format>`
-       parent structure with padding bytes at the end, are not affected.
+   This field was added in Linux 2.6.23, extending the
+   structure. However the :ref:`VIDIOC_[G|S|TRY]_FMT <VIDIOC_G_FMT>`
+   ioctls, which take a pointer to a :ref:`v4l2_format <v4l2-format>`
+   parent structure with padding bytes at the end, are not affected.
 
 
 .. _v4l2-clip: