clk: imx: Remove the snvs clock

The SNVS moudule is not used only by the linux, it may also used
by other SW component is secure world. No sense to populate it
in linux, so remove it.

Signed-off-by: Jacky Bai <ping.bai@nxp.com>
Reviewed-by: Abel Vesa <abel.vesa@nxp.com>
Link: https://lore.kernel.org/r/20220310093404.236966-1-ping.bai@nxp.com
Signed-off-by: Abel Vesa <abel.vesa@nxp.com>