[SCSI] fcoe: setup default initial value for DDP threshold

Currently fcoe_ddp_min doesn't have default value
so by default not used, so setting up default value
as 4k as this works better by avoiding overhead
of programing DDP for small IOs.

Signed-off-by: Vasu Dev <vasu.dev@intel.com>
Tested-by: Ross Brattain <ross.b.brattain@intel.com>
Signed-off-by: Yi Zou <yi.zou@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

drivers/scsi/fcoe/fcoe.c

@@ -52,7 +52,7 @@ MODULE_DESCRIPTION("FCoE");
 MODULE_LICENSE("GPL v2");
 
 /* Performance tuning parameters for fcoe */
-static unsigned int fcoe_ddp_min;
+static unsigned int fcoe_ddp_min = 4096;
 module_param_named(ddp_min, fcoe_ddp_min, uint, S_IRUGO | S_IWUSR);
 MODULE_PARM_DESC(ddp_min, "Minimum I/O size in bytes for "	\
 		 "Direct Data Placement (DDP).");