xilinx: versal: Add PSCI APIs for suspend/resume

Add following APIs in plat_psci to support suspend resume:
- versal_pwr_domain_off
- versal_pwr_domain_suspend
- versal_pwr_domain_suspend_finish
- versal_validate_power_state
- versal_get_sys_suspend_power_state

Signed-off-by: Tejas Patel <tejas.patel@xilinx.com>
Signed-off-by: Rajan Vaja <rajan.vaja@xilinx.com>
Signed-off-by: Jolly Shah <jolly.shah@xilinx.com>
Change-Id: Ife908a45f32e2037c9c19e13211a8e4b373b8342
diff --git a/plat/xilinx/versal/bl31_versal_setup.c b/plat/xilinx/versal/bl31_versal_setup.c
index 0deff90..6b56307 100644
--- a/plat/xilinx/versal/bl31_versal_setup.c
+++ b/plat/xilinx/versal/bl31_versal_setup.c
@@ -6,6 +6,7 @@
 
 #include <assert.h>
 #include <errno.h>
+#include <plat_arm.h>
 #include <plat_private.h>
 #include <bl31/bl31.h>
 #include <common/bl_common.h>
@@ -102,6 +103,9 @@
  */
 void bl31_plat_arch_setup(void)
 {
+	plat_arm_interconnect_init();
+	plat_arm_interconnect_enter_coherency();
+
 	const mmap_region_t bl_regions[] = {
 		MAP_REGION_FLAT(BL31_BASE, BL31_END - BL31_BASE,
 			MT_MEMORY | MT_RW | MT_SECURE),