armv8/fsl-lsch3: Suppress spurious warning on Layerscape CPUs

armv8/fsl-lsch3: Suppress spurious warning on Layerscape CPUs

NXP/Freescale Layerscape CPUs support high-speed serial interfaces (SERDES)
that can be configured for the application. Interfaces not used by the
application can be set to protocol 0 to turn them off and save power, but
U-Boot would emit a warning that 0 was invalid for a SERDES protocol on
boot. Replace the warning text with a notice that the SERDES is disabled.

Signed-off-by: Stephen Carlson <stcarlso@linux.microsoft.com>
Reviewed-by: Priyanka Jain <priyanka.jain@nxp.com>