This patch updates wake time of the cpu to use the MSBs and zero
out the LSB's. Only 24 out of 32 bits are currently passed
through the PSCI interface. Previously all the LSB's were used.

Change-Id: Ie2d9d1bf6e3003dd47526a124f64e6ad555d2371
Signed-off-by: Krishna Sitaraman <ksitaraman@nvidia.com>
Signed-off-by: Varun Wadekar <vwadekar@nvidia.com>