Rename sr_crypto_rw2() to sr_crypto_dev_rw(), which actually reflects the fact that it is used to generate I/O to the underlying device.
Rename sr_crypto_rw2() to sr_crypto_dev_rw(), which actually reflects the
fact that it is used to generate I/O to the underlying device.

Input from/ok krw@

orumin/openbsd-efivars,orumin/openbsd-efivars,orumin/openbsd-efivars,orumin/openbsd-efivars