ARM: dts: sun6i: Fix endpoint IDs in second display pipeline

When the second display pipeline device nodes for the A31/A31s were
added, it was not known that the TCONs could (through either DRCs)
select either backend as their input. Thus in the endpoints connecting
these components together, the endpoint IDs were set to 0, while in
fact they should have been set to 1.

Cc: <stable@vger.kernel.org>
Fixes: 9a26882a ("ARM: dts: sun6i: Add second display pipeline device
		      nodes")
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>