staging/lustre: Remove unused ll_vfs_* compat defines

Lustre defines quite a bit of those compatibility defines
duplicating kernel vfs api, but they are not actually used
in the client so remove them all and also ll_dirty_inode,
ll_security_inode_unlink and cfs_path_put

Signed-off-by: Oleg Drokin <oleg.drokin@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>