fs/erofs: Quieten test for filesystem presence
At present listing a partition produces lots of errors about this
filesystem:
=> part list mmc 4
cannot find valid erofs superblock
cannot find valid erofs superblock
cannot read erofs superblock: -5
[9 more similar lines]
Use debugging rather than errors when unable to find a signature, as is
done with other filesystems.
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>