feat(fvp): enable support for PSCI OS-initiated mode

Change-Id: I4cd6d2bd7ec7f581bd525d5323a3b54e855e2e51
Signed-off-by: Wing Li <wingers@google.com>
diff --git a/plat/arm/board/fvp/include/platform_def.h b/plat/arm/board/fvp/include/platform_def.h
index 039f8e2..84e2e82 100644
--- a/plat/arm/board/fvp/include/platform_def.h
+++ b/plat/arm/board/fvp/include/platform_def.h
@@ -30,6 +30,10 @@
 
 #define PLAT_MAX_PWR_LVL		ARM_PWR_LVL2
 
+#if PSCI_OS_INIT_MODE
+#define PLAT_MAX_CPU_SUSPEND_PWR_LVL	ARM_PWR_LVL1
+#endif
+
 /*
  * Other platform porting definitions are provided by included headers
  */