The short atom parser can return an errno from decoding but does not
currently return the error as a signed value. Convert all of the parsers
to ssize_t.
Signed-off-by: NJon Derrick <jonathan.derrick@intel.com>
Reviewed-by: NScott Bauer <scott.bauer@intel.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@fb.com>