feat(plat/mediatek/mt8186): initialize GIC

Initialize GIC for mt8186.

TEST=build pass
BUG=b:202871018

Signed-off-by: Christine Zhu <christine.zhu@mediatek.corp-partner.google.com>
Change-Id: I8d029983c7ce48fa116fafa7fa78c65349308014
diff --git a/plat/mediatek/mt8186/bl31_plat_setup.c b/plat/mediatek/mt8186/bl31_plat_setup.c
index 3734f91..6415cb7 100644
--- a/plat/mediatek/mt8186/bl31_plat_setup.c
+++ b/plat/mediatek/mt8186/bl31_plat_setup.c
@@ -17,6 +17,7 @@
 
 /* Platform Includes */
 #include <emi_mpu.h>
+#include <mt_gic_v3.h>
 #include <mt_timer.h>
 #include <plat_params.h>
 #include <plat_private.h>
@@ -82,6 +83,10 @@
  ******************************************************************************/
 void bl31_platform_setup(void)
 {
+	/* Initialize the GIC driver, CPU and distributor interfaces */
+	mt_gic_driver_init();
+	mt_gic_init();
+
 	mt_systimer_init();
 	generic_delay_timer_init();