tests: rename makefile directory to makefiles. (#8646)

Signed-off-by: Shanmin Zhang <zhangshanmin@xiaomi.com>

tests/makefiles/.gitignore

@@ -0,0 +1 @@
+test_file

tests/makefiles/Makefile

@@ -0,0 +1,10 @@
+LVGL_PATH := $(CURDIR)/../..
+$(info LVGL_PATH is set to: $(LVGL_PATH))
+include ../../lvgl.mk
+
+CSRCS += test.c
+CFLAGS += -Werror -DLV_CONF_SKIP=1 -DLV_BUILD_TEST=1 -I$(LVGL_PATH)/..
+COBJS := $(patsubst %.c, %.o, $(CSRCS))
+
+test_file: $(COBJS)
+	$(CC) -o $@ $^

tests/makefiles/test.c

@@ -0,0 +1,10 @@
+#if LV_BUILD_TEST
+#include <stdio.h>
+#include "../../lvgl.h"
+
+int main(void)
+{
+    lv_init();
+    return 0;
+}
+#endif