feat(s32g274a): enable BL31 stage

Add BL31 prerequisites for the S32G274ARDB2 board to allow single-core
cold boot without MMU and PSCI services.

Change-Id: I8a10fd62f3cc9430083758043ea82e3803f61060
Signed-off-by: Bogdan Hamciuc <bogdan.hamciuc@nxp.com>
Signed-off-by: Bogdan Roman <bogdan-gabriel.roman@nxp.com>
Signed-off-by: Andra-Teodora Ilie <andra.ilie@nxp.com>
Signed-off-by: Ghennadi Procopciuc <ghennadi.procopciuc@nxp.com>
diff --git a/plat/nxp/s32/s32g274ardb2/include/plat_helpers.h b/plat/nxp/s32/s32g274ardb2/include/plat_helpers.h
new file mode 100644
index 0000000..18582ec
--- /dev/null
+++ b/plat/nxp/s32/s32g274ardb2/include/plat_helpers.h
@@ -0,0 +1,12 @@
+/*
+ * Copyright 2024 NXP
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#ifndef PLAT_HELPERS_H
+#define PLAT_HELPERS_H
+
+unsigned int s32g2_core_pos_by_mpidr(u_register_t mpidr);
+
+#endif /* PLAT_HELPERS_H */