ocfs2: use common file type conversion

Deduplicate the ocfs2 file type conversion implementation and remove
OCFS2_FT_* definitions - file systems that use the same file types as
defined by POSIX do not need to define their own versions and can use the
common helper functions decared in fs_types.h and implemented in
fs_types.c

Common implementation can be found via bbe7449e ("fs: common
implementation of file type").

Link: http://lkml.kernel.org/r/20190326213919.GA20878@pathfinder


Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Phillip Potter <phil@philpotter.co.uk>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Joseph Qi <jiangqi903@gmail.com>
Cc: Changwei Ge <gechangwei@live.cn>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>