samples: littlefs: Add fs_file_t type variable initializations

The commit adds initializations of fs_file_t variables in preparation
for fs_open function change that will require fs_file_t object, passed
to the function, to be initialized before first usage.

Signed-off-by: Dominik Ermel <[email protected]>

Author: de-nordic

samples/subsys/fs/littlefs/src/main.c

@@ -99,6 +99,8 @@ void main(void)
 
 	struct fs_file_t file;
 
+	fs_file_t_init(&file);
+
 	rc = fs_open(&file, fname, FS_O_CREATE | FS_O_RDWR);
 	if (rc < 0) {
 		printk("FAIL: open %s: %d\n", fname, rc);