nilfs2: rename nilfs_recover_logical_segments function

The function name of nilfs_recover_logical_segments makes no sense.
This changes the name into nilfs_salvage_orphan_logs to clarify the
role of the function.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

diff --cc fs/nilfs2/recovery.c
Simple merge

diff --cc fs/nilfs2/segment.h
Simple merge

diff --cc fs/nilfs2/the_nilfs.c
Simple merge