Silicon/NXP: LS1043A: Add SerDes Support

Based on SerDes protocol value in reset configuration word (RCW)
different IP blocks gets enabled in HW.
Add SoC specific SerDes configuration for LS1043A, which can be
used by different IPs to know the enabled interfaces and perform
the required initialization.

Signed-off-by: Wasim Khan <wasim.khan@nxp.com>
Reviewed-by: Leif Lindholm <leif@nuviainc.com>