dt-bindings: imx: update clock doc for imx6sll

Add clock binding doc update for imx6sll.

Signed-off-by: Bai Ping <ping.bai@nxp.com>
Acked-by: Dong Aisheng <aisheng.dong@nxp.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
2 files changed