extmod/vfs_lfsx: Fix path handling in uos.stat() to consider cur dir.

This fixes the bug, that stat(filename) would not consider the current
working directory.  So if e.g. the cwd is "lib", then stat("main.py") would
return the info for "/main.py" instead of "/lib/main.py".

extmod/vfs_lfsx.c

@@ -304,7 +304,7 @@ STATIC MP_DEFINE_CONST_FUN_OBJ_1(MP_VFS_LFSx(getcwd_obj), MP_VFS_LFSx(getcwd));
 
 STATIC mp_obj_t MP_VFS_LFSx(stat)(mp_obj_t self_in, mp_obj_t path_in) {
     MP_OBJ_VFS_LFSx *self = MP_OBJ_TO_PTR(self_in);
-    const char *path = mp_obj_str_get_str(path_in);
+    const char *path = MP_VFS_LFSx(make_path)(self, path_in);
     struct LFSx_API (info) info;
     int ret = LFSx_API(stat)(&self->lfs, path, &info);
     if (ret < 0) {

tests/extmod/vfs_lfs.py

@@ -101,6 +101,14 @@ def test(bdev, vfs_class):
     print(vfs.getcwd())
     vfs.chdir("/testdir")
     print(vfs.getcwd())
+
+    # create file in directory to make sure paths are relative
+    vfs.open("test2", "w").close()
+    print(vfs.stat("test2"))
+    print(vfs.stat("/testdir/test2"))
+    vfs.remove("test2")
+
+    # chdir back to root and remove testdir
     vfs.chdir("/")
     print(vfs.getcwd())
     vfs.rmdir("testdir")

tests/extmod/vfs_lfs.py.exp

@@ -20,6 +20,8 @@ write 3
 [('test', 32768, 0, 8), ('testdir', 16384, 0, 0)]
 /
 /testdir
+(32768, 0, 0, 0, 0, 0, 0, 0, 0, 0)
+(32768, 0, 0, 0, 0, 0, 0, 0, 0, 0)
 /
 test <class 'VfsLfs2'>
 (1024, 1024, 30, 28, 28, 0, 0, 0, 0, 255)
@@ -43,4 +45,6 @@ write 3
 [('testdir', 16384, 0, 0), ('test', 32768, 0, 8)]
 /
 /testdir
+(32768, 0, 0, 0, 0, 0, 0, 0, 0, 0)
+(32768, 0, 0, 0, 0, 0, 0, 0, 0, 0)
 /