- remove err_mask from the parameter list of the complete functions
  - move err_mask to ata_queued_cmd
  - initialize qc->err_mask when needed
  - for each function call to ata_qc_complete(), replace the err_mask parameter with qc->err_mask.
Signed-off-by: Albert Lee <albertcc@tw.ibm.com>

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Signed-off-by: Jeff Garzik <jgarzik@pobox.com>