scsi: qla2xxx: Remove a declaration

Since there is no definition for the qla2x00_host_attrs_dm array, remove
its declaration.

Link: https://lore.kernel.org/r/20211012233558.4066756-40-bvanassche@acm.orgSigned-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/qla2xxx/qla_gbl.h

@@ -743,7 +743,6 @@ uint qla25xx_fdmi_port_speed_currently(struct qla_hw_data *);
  */
 struct device_attribute;
 extern struct device_attribute *qla2x00_host_attrs[];
-extern struct device_attribute *qla2x00_host_attrs_dm[];
 struct fc_function_template;
 extern struct fc_function_template qla2xxx_transport_functions;
 extern struct fc_function_template qla2xxx_transport_vport_functions;