feat(mediatek): add smcc call for MSDC

Some registers of MSDC need to be set in ATF, so we add MSDC drivers.

Signed-off-by: Bo-Chen Chen <rex-bc.chen@mediatek.com>
Change-Id: Idde51a136ad08dbaece0bdaa804b934fca7046b6
diff --git a/plat/mediatek/mt8186/plat_sip_calls.c b/plat/mediatek/mt8186/plat_sip_calls.c
index d9144d8..0e9c270 100644
--- a/plat/mediatek/mt8186/plat_sip_calls.c
+++ b/plat/mediatek/mt8186/plat_sip_calls.c
@@ -6,6 +6,8 @@
 
 #include <common/debug.h>
 #include <common/runtime_svc.h>
+#include <lib/mmio.h>
+#include <mt_msdc.h>
 #include <mt_spm_vcorefs.h>
 #include <mtk_sip_svc.h>
 #include <plat_dfd.h>
@@ -33,6 +35,11 @@
 		ret = dfd_smc_dispatcher(x1, x2, x3, x4);
 		SMC_RET1(handle, ret);
 		break;
+	case MTK_SIP_KERNEL_MSDC_AARCH32:
+	case MTK_SIP_KERNEL_MSDC_AARCH64:
+		ret = msdc_smc_dispatcher(x1, x2, x3, x4);
+		SMC_RET1(handle, ret);
+		break;
 	default:
 		ERROR("%s: unhandled SMC (0x%x)\n", __func__, smc_fid);
 		break;