fix --savedir error
fix --savedir error

python3 ubidump.py --savedir fs1  test.img
==> test.img <==
named volumes found, 2 physical volumes, blocksize=0x20000
== volume b'testfs' ==
E: [Errno 2] No such file or directory: b'fs1/fs1/test.txt'
nlitsme/ubidump