powerpc/corenet_ds: display the RCW at boot

Display the 64-byte Reset Configuration Word (RCW) during boot, so that
there's no confusion as to what RCW U-boot is using.

Reset Configuration Word (RCW):
       00000000: 4a500000 00000000 18181818 00008888
       00000010: 28402400 00002000 fe800000 01200000
       00000020: 00000000 00000000 00000000 000b0000
       00000030: 00000000 00000000 00000000 00000000

Signed-off-by: Timur Tabi <timur@freescale.com>
Signed-off-by: Roy Zang <tie-fei.zang@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>