Add support for PSCI SYSTEM_OFF and SYSTEM_RESET APIs

This patch adds support for SYSTEM_OFF and SYSTEM_RESET PSCI
operations. A platform should export handlers to complete the
requested operation. The FVP port exports fvp_system_off() and
fvp_system_reset() as an example.

If the SPD provides a power management hook for system off and
system reset, then the SPD is notified about the corresponding
operation so it can do some bookkeeping. The TSPD exports
tspd_system_off() and tspd_system_reset() for that purpose.

Versatile Express shutdown and reset methods have been removed
from the FDT as new PSCI sys_poweroff and sys_reset services
have been added. For those kernels that do not support yet these
PSCI services (i.e. GICv3 kernel), the original dtsi files have
been renamed to *-no_psci.dtsi.

Fixes ARM-software/tf-issues#218

Change-Id: Ic8a3bf801db979099ab7029162af041c4e8330c8
diff --git a/fdts/rtsm_ve-motherboard.dtsi b/fdts/rtsm_ve-motherboard.dtsi
index 7ba575e..6aa40ff 100644
--- a/fdts/rtsm_ve-motherboard.dtsi
+++ b/fdts/rtsm_ve-motherboard.dtsi
@@ -236,25 +236,37 @@
 				clock-output-names = "v2m:oscclk1";
 			};
 
-			reset@0 {
-				compatible = "arm,vexpress-reset";
-				arm,vexpress-sysreg,func = <5 0>;
-			};
+			/*
+			 * Not supported in FVP models
+			 *
+			 * reset@0 {
+			 * 	compatible = "arm,vexpress-reset";
+			 * 	arm,vexpress-sysreg,func = <5 0>;
+			 * };
+			 */
 
 			muxfpga@0 {
 				compatible = "arm,vexpress-muxfpga";
 				arm,vexpress-sysreg,func = <7 0>;
 			};
 
-			shutdown@0 {
-				compatible = "arm,vexpress-shutdown";
-				arm,vexpress-sysreg,func = <8 0>;
-			};
+			/*
+			 * Not used - Superseded by PSCI sys_poweroff
+			 *
+			 * shutdown@0 {
+			 * 	compatible = "arm,vexpress-shutdown";
+			 * 	arm,vexpress-sysreg,func = <8 0>;
+			 * };
+			 */
 
-			reboot@0 {
-				compatible = "arm,vexpress-reboot";
-				arm,vexpress-sysreg,func = <9 0>;
-			};
+			/*
+			 * Not used - Superseded by PSCI sys_reset
+			 *
+			 * reboot@0 {
+			 * 	compatible = "arm,vexpress-reboot";
+			 * 	arm,vexpress-sysreg,func = <9 0>;
+			 * };
+			 */
 
 			dvimode@0 {
 				compatible = "arm,vexpress-dvimode";