Btrfs: fix to catch all errors when resolving indirect ref

We can only tolerate ENOENT here, for other errors, we should
return directly.

Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>