psci: Use context library for preserving EL3 state
Achin Gupta authored
This patch uses the context library to save and restore EL3 state on
the 'cpu_context' data structures allocated by PSCI for managing
non-secure state context on each cpu.

Change-Id: I19c1f26578204a7cd9e0a6c582ced0d97ee4cf80
ef7a28c9