erofs-utils: fix cross-device submounts

Use device ID and inode number to identify hardlinks
rather than inode number only.

Link: https://lore.kernel.org/r/20201204175642.3231-1-hsiangkao@aol.com
Fixes: a17497f0844a ("erofs-utils: introduce inode operations")
Reviewed-by: Li Guifu <bluce.lee@aliyun.com>
Signed-off-by: Gao Xiang <hsiangkao@aol.com>
2 files changed