[SCSI] qla4xxx: Reset seconds_since_last_heartbeat correctly.

[SCSI] qla4xxx: Reset seconds_since_last_heartbeat correctly.

The seconds_since_last_heartbeat should be checked for consecutive
heartbeat checks. Currently it could happen that it gets set to
max (2 seconds) for non-consecutive heartbeat checks.

Signed-off-by: Vikas Chaudhary <vikas.chaudhary@qlogic.com>
Signed-off-by: Lalit Chandivade <lalit.chandivade@qlogic.com>
Signed-off-by: Ravi Anand <ravi.anand@qlogic.com>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>