ARM: dts: ls1021a-qds: Remove extra clock cell

There is an extraneous '1' cell in the clock phandle, which causes
the following build warning:

arch/arm/boot/dts/ls1021a-qds.dtb: Warning (clocks_property): Property 'clocks', cell 1 is not a phandle reference in /soc/i2c@2180000/mux@77/i2c@4/sgtl5000@2a
arch/arm/boot/dts/ls1021a-qds.dtb: Warning (clocks_property): Missing property '#clock-cells' in node /soc/interrupt-controller@1400000 or bad phandle (referred from /soc/i2c@2180000/mux@77/i2c@4/sgtl5000@2a:clocks[1])

Remove the unneeded extra cell.

Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>