Update LVGL to v9.1.0

lib/lvgl/tests/makefile/.gitignore

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

lib/lvgl/tests/makefile/Makefile

@@ -1,8 +1,9 @@
-LVGL_DIR := $(CURDIR)/../..
+LVGL_PATH := $(CURDIR)/../..
+$(info LVGL_PATH is set to: $(LVGL_PATH))
 include ../../lvgl.mk
 
 CSRCS += test.c
-CFLAGS += -DLV_CONF_SKIP=1 -DLV_BUILD_TEST=1 -I$(LVGL_DIR)/..
+CFLAGS += -Werror -DLV_CONF_SKIP=1 -DLV_BUILD_TEST=1 -DLV_USE_DEV_VERSION -I$(LVGL_PATH)/..
 COBJS := $(patsubst %.c, %.o, $(CSRCS))
 
 test_file: $(COBJS)

lib/lvgl/tests/makefile/test.c

@@ -1,8 +1,9 @@
 #if LV_BUILD_TEST
 #include <stdio.h>
-#include "lvgl/lvgl.h"
+#include "../../lvgl.h"
 
-int main(void) {
+int main(void)
+{
     lv_init();
     return 0;
 }