lkl tools: lib: fix lkl_opendir error reporting

The error code was not properly initialized in case of success or when
we don't have enough memory to allocate the lkl_dir structure.

Signed-off-by: Octavian Purdila <tavi@cs.pub.ro>

tools/lkl/lib/fs.c

@@ -335,8 +335,10 @@ struct lkl_dir *lkl_opendir(const char *path, int *err)
 {
 	struct lkl_dir *dir = lkl_dir_alloc(err);
 
-	if (!dir)
+	if (!dir) {
+		*err = -LKL_ENOMEM;
 		return NULL;
+	}
 
 	dir->fd = lkl_sys_open(path, LKL_O_RDONLY | LKL_O_DIRECTORY, 0);
 	if (dir->fd < 0) {
@@ -345,6 +347,8 @@ struct lkl_dir *lkl_opendir(const char *path, int *err)
 		return NULL;
 	}
 
+	*err = 0;
+
 	return dir;
 }