[PATCH] libata-dev: Use new AC_ERR_* flags

  - Use new AC_ERR_* flags as done in Tejun's patches
  - In ata_qc_timeout(), replace ac_err_mask(drv_stat) with AC_ERR_TIMEOUT.
    This makes time out handler always report error to upper layer.
    Otherwise if the drv_stat looks good, libata might falsely report OK to the upper layer.

Signed-off-by: Albert Lee <albertcc@tw.ibm.com>
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Signed-off-by: Jeff Garzik <jgarzik@pobox.com>