Increment the PSCI VERSION to 1.0

This patch:

   * Bumps the PSCI VERSION to 1.0. This means that
     the PSCI_VERSION API will now return the value 0x00010000
     to indicate the version as 1.0. The firmware remains
     compatible with PSCI v0.2 clients.

   * The firmware design guide is updated to document the
     APIs supported by the Trusted Firmware generic code.

   * The FVP Device Tree Sources (dts) and Blobs(dtb) are also
     updated to add "psci-1.0" and "psci-0.2" to the list of
     compatible PSCI versions.

Change-Id: Iafc2f549c92651dcd65d7e24a8aae35790d00f8a
diff --git a/fdts/fvp-foundation-gicv2legacy-psci.dts b/fdts/fvp-foundation-gicv2legacy-psci.dts
index a923c34..8dba04c 100644
--- a/fdts/fvp-foundation-gicv2legacy-psci.dts
+++ b/fdts/fvp-foundation-gicv2legacy-psci.dts
@@ -83,7 +83,7 @@
 		};
 
 		idle-states {
-			entry-method = "arm,psci";
+			entry-method = "arm,psci-1.0", "arm,psci-0.2", "arm,psci";
 
 			CPU_SLEEP_0: cpu-sleep-0 {
 				compatible = "arm,idle-state";