ARM: dts: imx53-qsb: Let the codec control MCLK pinctrl

The hog pinctrl hog is meant for pins that do not have an
associated driver.

The MX53_PAD_GPIO_0__CCM_SSI_EXT1_CLK pin is the one that
provides the MCLK signal to the SGTL5000 codec, so a
better represenation is to move it under the codec node.

While at it, change the pinctrl value from 0x80000000 to the
POR reset value of register IOMUXC_SW_PAD_CTL_PAD_GPIO_0.

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