Ensure fd is really waiting for read

If the wire will not be in waiting state the wire_fd may turn off the
read state.
Read the clock immediately after read returned
Show sense on disk scan error
Debug prints for inquiry
Reduce buffer size to make ATA IDENTIFY always work

When requesting ATA IDENTIFY we always get exactly 512 bytes by spec. If
I request 4096 bytes from the controller the request seems to be lost in
some controllers. Always request 512 bytes to make it work consistently.