nitrogen6x: Setup CCM_CCOSR register

nitrogen6x: Setup CCM_CCOSR register

CKO1 drives sgtl5000 codec clock on nitrogen boards and wandboard.

Doing this setup in the bootloader will allow us to remove a lot of code in
arch/arm/mach-imx/mach-imx6q.c from the mainline kernel.

Also, according to Eric Nelson: "enabling the clock <in the bootloader> will
remove squeal after an ungraceful reboot (watchdog) if hooked up to speakers."

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>