Per-cpu data cache restructuring

This patch prepares the per-cpu pointer cache for wider use by:
* renaming the structure to cpu_data and placing in new header
* providing accessors for this CPU, or other CPUs
* splitting the initialization of the TPIDR pointer from the
  initialization of the cpu_data content
* moving the crash stack initialization to a crash stack function
* setting the TPIDR pointer very early during boot

Change-Id: Icef9004ff88f8eb241d48c14be3158087d7e49a3
diff --git a/include/bl31/runtime_svc.h b/include/bl31/runtime_svc.h
index d7d88d4..3b84f06 100644
--- a/include/bl31/runtime_svc.h
+++ b/include/bl31/runtime_svc.h
@@ -267,7 +267,8 @@
 void runtime_svc_init();
 extern uint64_t __RT_SVC_DESCS_START__;
 extern uint64_t __RT_SVC_DESCS_END__;
-uint64_t get_crash_stack(uint64_t mpidr);
+void init_crash_reporting(void);
 void runtime_exceptions(void);
+
 #endif /*__ASSEMBLY__*/
 #endif /* __RUNTIME_SVC_H__ */