arm64: dts: sprd: fix typo in 'remote-endpoint'

dtc now warns on incomplete OF graph endpoint connections:

arch/arm64/boot/dts/sprd/sp9860g-1h10.dtb: Warning (graph_endpoint): /soc/stm@10006000/port/endpoint: graph connection to node '/soc/funnel@10001000/ports/port@2/endpoint' is not bidirectional

The cause is a typo in 'remote-endpoint'.

Cc: Orson Zhai <orsonzhai@gmail.com>
Cc: Baolin Wang <baolin.wang@linaro.org>
Cc: Chunyan Zhang <zhang.lyra@gmail.com>
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Olof Johansson <olof@lixom.net>