reiserfs: switch reiserfs_readdir_dentry to inode

... and clean the callers up a bit

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

diff --cc fs/reiserfs/dir.c
Simple merge

diff --cc fs/reiserfs/reiserfs.h
Simple merge

diff --cc fs/reiserfs/xattr.c
Simple merge