feat(mt8186): add SPM suspend driver

Add SPM suspend driver for suspend/resume features.

TEST=build pass
BUG=b:202871018

Change-Id: I25b4b97cd3138a7b347385539e47ccfa884d64fc
diff --git a/plat/mediatek/mt8186/drivers/spm/notifier/mt_spm_notifier.h b/plat/mediatek/mt8186/drivers/spm/notifier/mt_spm_notifier.h
new file mode 100644
index 0000000..89aa163
--- /dev/null
+++ b/plat/mediatek/mt8186/drivers/spm/notifier/mt_spm_notifier.h
@@ -0,0 +1,23 @@
+/*
+ * Copyright (c) 2022, MediaTek Inc. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#ifndef MT_SPM_SSPM_NOTIFIER_H
+#define MT_SPM_SSPM_NOTIFIER_H
+
+enum MT_SPM_SSPM_NOTIFY_ID {
+	MT_SPM_NOTIFY_LP_ENTER			= 0U,
+	MT_SPM_NOTIFY_LP_LEAVE			= 1U,
+	MT_SPM_NOTIFY_SUSPEND_VCORE_VOLTAGE	= 2U,
+};
+
+int mt_spm_sspm_notify(int type, unsigned int lp_mode);
+
+static inline int mt_spm_sspm_notify_u32(int type, unsigned int lp_mode)
+{
+	return mt_spm_sspm_notify(type, lp_mode);
+}
+
+#endif /* MT_SPM_SSPM_NOTIFIER_H */