The container node in the iomuxc node is no longer necessary and causes
pinctl errors on the Ventana boards with analog video capture
since aa12693e:

pinctrl core: initialized pinctrl subsystem
imx6q-pinctrl 20e0000.iomuxc: no groups defined in /soc/aips-bus@02000000/iomuxc@020e0000/adv7180grp
imx6q-pinctrl 20e0000.iomuxc: no groups defined in /soc/aips-bus@02000000/iomuxc@020e0000/ipu2_csi1grp
imx6q-pinctrl 20e0000.iomuxc: initialized IMX pinctrl driver
imx6q-pinctrl 20e0000.iomuxc: function 'iomuxc' not supported
imx6q-pinctrl 20e0000.iomuxc: invalid function iomuxc in map table
imx6q-pinctrl 20e0000.iomuxc: function 'iomuxc' not supported
imx6q-pinctrl 20e0000.iomuxc: invalid function iomuxc in map table
Signed-off-by: Tim Harvey <tharvey@gateworks.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>