mips: add base support for QCA/Atheros ath79 SOCs

This patch add some common code for QCA/Atheros ath79 SOCs such as
DDR tuning, chip reset and CPU detection.

Signed-off-by: Wills Wang <wills.wang@live.com>
diff --git a/arch/mips/mach-ath79/Makefile b/arch/mips/mach-ath79/Makefile
new file mode 100644
index 0000000..6203cf0
--- /dev/null
+++ b/arch/mips/mach-ath79/Makefile
@@ -0,0 +1,7 @@
+#
+# SPDX-License-Identifier:	GPL-2.0+
+#
+
+obj-y += reset.o
+obj-y += cpu.o
+obj-y += dram.o