imx: mx6: ccm: Change the clock settings for i.MX6QP

Since i.MX6QP changes some CCM registers, so modify the clocks settings to
follow the hardware changes.

In c files, use runtime check and discard #ifdef.

Signed-off-by: Peng Fan <Peng.Fan@freescale.com>
Signed-off-by: Ye.Li <B37916@freescale.com>
Reviewed-by: Fabio Estevam <fabio.estevam@freescale.com>
Acked-by: Stefano Babic <sbabic@denx.de>