[SCSI] qla2xxx: Correct eh_abort recovery logic.

Fix the driver to return SUCCESS if the firmware or driver doesn't
have a command to abort, i.e., it's already been returned.  Without
this patch, error recovery will take the target offline as it tries
harder and harder to get the driver to return the command it no longer
has.

Signed-off-by: Andrew Vasquez <andrew.vasquez@qlogic.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>