This patch saves the 'power_state' parameter prior to suspending
a cpu and invalidates it upon its resumption. The 'affinity level'
and 'state id' fields of this parameter can be read using a set of
public and private apis. Validation of power state parameter is
introduced which checks for SBZ bits are zero.
This change also takes care of flushing the parameter from the cache
to main memory. This ensures that it is available after cpu reset
when the caches and mmu are turned off. The earlier support for
saving only the 'affinity level' field of the 'power_state' parameter
has also been reworked.
FixesARM-Software/tf-issues#26FixesARM-Software/tf-issues#130
Change-Id: Ic007ccb5e39bf01e0b67390565d3b4be33f5960a
759ec93b69