commit 72649a46 upstream.

According to the schematics of CompuLab's sbc-fx6 baseboard and the
vendor devicetree GPIO_16 is *not* muxed to ENET_REF_CLK but to SPDIF_IN.

Remove the wrong pinctrl setting.

Fixes: 682d055e ("ARM: dts: Add initial support for cm-fx6.")
Signed-off-by: Christopher Spinrath <christopher.spinrath@rwth-aachen.de>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
[bwh: Backported to 3.16: adjust indentation]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>