powerpc/t104xrdb: Toggle deep sleep management signals after resume

T104xrdb has several sleep management signals that are used for deep
sleep. They are enabled by OS to enter deep sleep and should be
disabled by u-boot when cores wake up.

Signed-off-by: Tang Yuantian <Yuantian.Tang@freescale.com>
Reviewed-by: York Sun <yorksun@freescale.com>