[SCSI] qla2xxx: Properly set the return value in qla2xxx_eh_abort function.

A return value is not set for the successful case and it has a garbage value.
This fix will set the default value to SUCCESS and in case of any failures
it is changed.

Signed-off-by: Saurav Kashyap <saurav.kashyap@qlogic.com>
Signed-off-by: Madhuranath Iyengar <Madhu.Iyengar@qlogic.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>