linux/ethtool: Added macro ETH_FW_DUMP_DISABLE

o flag field of ethtool_dump structure must be initialized by this macro
value that is zero, if the firmware dump is disabled.
by this we can get the firmware dump capability [enable/disable] via ethtool
Signed-off-by: NManish chopra <manish.chopra@qlogic.com>
Reviewed-by: NBen Hutchings <bhutchings@solarflare.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

include/linux/ethtool.h

@@ -678,12 +678,17 @@ struct ethtool_flash {
  * 	%ETHTOOL_SET_DUMP
  * @version: FW version of the dump, filled in by driver
  * @flag: driver dependent flag for dump setting, filled in by driver during
- * 	  get and filled in by ethtool for set operation
+ *        get and filled in by ethtool for set operation.
+ *        flag must be initialized by macro ETH_FW_DUMP_DISABLE value when
+ *        firmware dump is disabled.
  * @len: length of dump data, used as the length of the user buffer on entry to
  * 	 %ETHTOOL_GET_DUMP_DATA and this is returned as dump length by driver
  * 	 for %ETHTOOL_GET_DUMP_FLAG command
  * @data: data collected for get dump data operation
  */
+
+#define ETH_FW_DUMP_DISABLE 0
+
 struct ethtool_dump {
 	__u32	cmd;
 	__u32	version;