ARM: dts: imx6ul-geam: fix fsl,pins property in tscgrp pinctrl

ARM: dts: imx6ul-geam: fix fsl,pins property in tscgrp pinctrl

The property is "fsl,pins", not "fsl,pin".  Wrong property means the pin
configuration was not applied.  Fixes dtbs_check warnings:

  imx6ul-geam.dtb: pinctrl@20e0000: tscgrp: 'fsl,pins' is a required property
  imx6ul-geam.dtb: pinctrl@20e0000: tscgrp: 'fsl,pin' does not match any of the regexes: 'pinctrl-[0-9]+'

Cc: stable@vger.kernel.org
Fixes: a58e4e608bc8 ("ARM: dts: imx6ul-geam: Add Engicam IMX6UL GEA M6UL initial support")
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Michael Trimarchi <michael@amarulasolutions.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>