erofs-utils: fix memory leak when get blob chunk

Release memory allocated for chunk before return error.

Link: https://lore.kernel.org/r/20211117102120.30203-2-huangjianan@oppo.com
Signed-off-by: Huang Jianan <huangjianan@oppo.com>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
1 file changed