No functional changes
* Move + Rename scsi command emulation out of idetask to scsi.c
* Move ATAPI SCSI command handling out of idetask to atapi.c
* Rename idetask to iotask
* Fix atapi_check_wp which was not working at all
* Check and handle sense code in atapi_test_unit_ready and atapi_translate
* Add retries for atapi_test_unit_ready and atapi_translate depending on sense code returned
* Add busy wait to atapi_dev_reset