MIPS: add initial infrastructure for device-tree files

Prepare sub-folder for device-tree files. Make support for
device-tree on MIPS available in Kbuild/Kconfig.

Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Signed-off-by: Purna Chandra Mandal <purna.mandal@microchip.com>
diff --git a/arch/mips/dts/Makefile b/arch/mips/dts/Makefile
new file mode 100644
index 0000000..47b6eb5
--- /dev/null
+++ b/arch/mips/dts/Makefile
@@ -0,0 +1,16 @@
+#
+# SPDX-License-Identifier:	GPL-2.0+
+#
+
+dtb-y +=
+
+targets += $(dtb-y)
+
+# Add any required device tree compiler flags here
+DTC_FLAGS +=
+
+PHONY += dtbs
+dtbs: $(addprefix $(obj)/, $(dtb-y))
+	@:
+
+clean-files := *.dtb