MFV r275545:
If zio_checksum_error() returns other than ECKSUM (e.g. EINVAL), it does not
fill in the "zio_bad_cksum_t *info" parameter. Caller should not attempt to
use it in this case.
Illumos issue:
5348 zio_checksum_error() only fills in info if ECKSUM
MFC after: 2 weeks