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/fvp-base-gicv3-psci.dts b/fdts/fvp-base-gicv3-psci.dts
index d111a99..44339a1 100644
--- a/fdts/fvp-base-gicv3-psci.dts
+++ b/fdts/fvp-base-gicv3-psci.dts
@@ -229,7 +229,7 @@
 				<0 0 41 &gic 0 0 0 41 4>,
 				<0 0 42 &gic 0 0 0 42 4>;
 
-		/include/ "rtsm_ve-motherboard.dtsi"
+		/include/ "rtsm_ve-motherboard-no_psci.dtsi"
 	};
 
 	panels {