armv8: lsch3: Add support of serdes3 module

Some lsch3 based SoCs like lx2160a contains three
serdes modules.
Add support for third serdes protocol in lsch3

Signed-off-by: Priyanka Jain <priyanka.jain@nxp.com>
Reviewed-by: York Sun <york.sun@nxp.com>
3 files changed