[SCSI] Revert "[SCSI] libfc: fix exchange being deleted when the abort itself is timed out"

When abort for an exchange timed out it didn't release the reference to
the exchange resulting in a memory leak.

After discussion with the author of the patch (CC) that introduced this
bug it was suggested to revert that patch.

This reverts commit ea3e2e72.

Signed-off by: Neerav Parikh <Neerav.Parikh@intel.com>
Tested-by: Ross Brattain <ross.b.brattain@intel.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>