cam: Fail ASC 0x40

ASC 0x40 is use to report diagnostics (as in the self test the drive
runs on itself) failures. The ASCQ code is the part that failed. These
failures are such that I/O to the drive's LBA range is not possible, so
make this condition fatal, and signal the drive's ill health.

Sponsored by: Netflix
Reviewed by: ken, mav
Differential Revision: https://reviews.freebsd.org/D48684