libion: add libion support in buildroot [2/3]

PD#SWPL-7758

Problem:
buildroot need libion shared library

Solution:
add libion

Verify:
verified on g12a-u200

Change-Id: I4b5f41464a74078494f68b2b8535f014b29520c6
Signed-off-by: Dezhi Kong <dezhi.kong@amlogic.com>
diff --git a/Makefile b/Makefile
new file mode 100644
index 0000000..3f7a28e
--- /dev/null
+++ b/Makefile
@@ -0,0 +1,28 @@
+#
+## makefile for libion and iontest
+#
+LIBION_OBJ = ion.o IONmem.o
+CFLAGS += -I ./include/
+CFLAGS += -I ./kernel-headers/
+LIBION = libion.so
+
+IONTEST_OBJ = ion_test.o
+IONTEST = iontest
+
+.PHONY: clean
+
+# rules
+all: $(LIBION) $(IONTEST)
+
+%.o: %.c
+	$(CC) -c -fPIC  $(CFLAGS) $^ -o $@
+
+$(LIBION): $(LIBION_OBJ)
+	$(CC) -shared -fPIC $(CFLAGS) $^ -o $(LIBION)
+
+$(IONTEST): $(IONTEST_OBJ) $(LIBION)
+	$(CC) $^ $(CFLAGS)  -o $@
+
+clean:
+	rm -f $(OBJ)
+