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The following is introduced in the patch
1. Enable GPT translation tables
2. Adds a new context for Realm world and adds realm world awareness in context management
3. Initializes CPU registers in context management for Realm world
Signed-off-by: John Powell <john.powell@arm.com>
Change-Id: I5bc8f3413144fb63d9eb4f5885abdcf5a44b4db1