drm/mcde: Fix Sphinx formatting

- Format the pipe diagram as a monospace block.
- Fix formatting of the list. Without the empty line, the first dash is
  not parsed as a bullet point.
Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20200214163815.25442-1-j.neuschaefer@gmx.net

drivers/gpu/drm/mcde/mcde_drv.c

@@ -20,7 +20,7 @@
  * input formats including most variants of RGB and YUV.
  *
  * The hardware has four display pipes, and the layout is a little
- * bit like this:
+ * bit like this::
  *
  *   Memory     -> Overlay -> Channel -> FIFO -> 5 formatters -> DSI/DPI
  *   External      0..5       0..3       A,B,    3 x DSI         bridge
@@ -43,6 +43,7 @@
  * to change as we exploit more of the hardware capabilities.
  *
  * TODO:
+ *
  * - Enabled damaged rectangles using drm_plane_enable_fb_damage_clips()
  *   so we can selectively just transmit the damaged area to a
  *   command-only display.