nxp: platform files for bl2 and bl31 setup

For NXP platforms:
- Setup files for BL2 and BL31
- Other supporting files.

Signed-off-by: Pankaj Gupta <pankaj.gupta@nxp.com>
Change-Id: I36a1183a0652701bdede9e02d41eb976accbb017
diff --git a/plat/nxp/common/setup/core.mk b/plat/nxp/common/setup/core.mk
new file mode 100644
index 0000000..9b81f2d
--- /dev/null
+++ b/plat/nxp/common/setup/core.mk
@@ -0,0 +1,20 @@
+# Copyright 2018-2020 NXP
+#
+# SPDX-License-Identifier: BSD-3-Clause
+#
+#
+#------------------------------------------------------------------------------
+#
+# Select the CORE files
+#
+# -----------------------------------------------------------------------------
+
+CPU_LIBS		:=	lib/cpus/${ARCH}/aem_generic.S
+
+ifeq (,$(filter $(CORE_TYPE),a53 a55 a57 a72 a75))
+$(error "CORE_TYPE not specified or incorrect")
+else
+CPU_LIBS		+=	lib/cpus/${ARCH}/cortex_$(CORE_TYPE).S
+endif
+
+# -----------------------------------------------------------------------------