libmount: don't canonicalize symlinks for bind operation

libmount: don't canonicalize symlinks for bind operation

The new kernel mount API can bind over symlink by default.

Unfortunately, libmount always canonicalizes all paths (due to
backward compatibility, search in mountinfo, search in fstab, etc.).

Possible workaround is -c, --no-canonicalize but it disable all paths
canonicalization, tags to paths conversions etc.

This patch disables the canonicalization only for the target path
(if symlink) on bind operation.

Fixes: https://github.com/util-linux/util-linux/issues/2370
Signed-off-by: Karel Zak <kzak@redhat.com>