Split platform.h into separate headers

Previously, platform.h contained many declarations and definitions
used for different purposes. This file has been split so that:

* Platform definitions used by common code that must be defined
  by the platform are now in platform_def.h. The exact include
  path is exported through $PLAT_INCLUDES in the platform makefile.

* Platform definitions specific to the FVP platform are now in
  /plat/fvp/fvp_def.h.

* Platform API declarations specific to the FVP platform are now
  in /plat/fvp/fvp_private.h.

* The remaining platform API declarations that must be ported by
  each platform are still in platform.h but this file has been
  moved to /include/plat/common since this can be shared by all
  platforms.

Change-Id: Ieb3bb22fbab3ee8027413c6b39a783534aee474a
diff --git a/include/lib/aarch64/arch.h b/include/lib/aarch64/arch.h
index 920dfc9..d89b4fe 100644
--- a/include/lib/aarch64/arch.h
+++ b/include/lib/aarch64/arch.h
@@ -394,4 +394,19 @@
 
 #define EC_BITS(x)			(x >> ESR_EC_SHIFT) & ESR_EC_MASK
 
+/*******************************************************************************
+ * Definitions of register offsets and fields in the CNTCTLBase Frame of the
+ * system level implementation of the Generic Timer.
+ ******************************************************************************/
+#define CNTNSAR			0x4
+#define CNTNSAR_NS_SHIFT(x)	x
+
+#define CNTACR_BASE(x)		(0x40 + (x << 2))
+#define CNTACR_RPCT_SHIFT	0x0
+#define CNTACR_RVCT_SHIFT	0x1
+#define CNTACR_RFRQ_SHIFT	0x2
+#define CNTACR_RVOFF_SHIFT	0x3
+#define CNTACR_RWVT_SHIFT	0x4
+#define CNTACR_RWPT_SHIFT	0x5
+
 #endif /* __ARCH_H__ */