[SCSI] zfcp: enable FCP hardware data router by default

Enabling the data router support by default
can increase performance in certain situations.
It is safe to do so and tolerated in LPAR and under z/VM
in case there is no data router support in that environment.
Signed-off-by: NSteffen Maier <maier@linux.vnet.ibm.com>
Reviewed-by: NMartin Peschke <mpeschke@linux.vnet.ibm.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

drivers/s390/scsi/zfcp_qdio.c

@@ -16,9 +16,9 @@
 
 #define QBUFF_PER_PAGE		(PAGE_SIZE / sizeof(struct qdio_buffer))
 
-static bool enable_multibuffer;
+static bool enable_multibuffer = 1;
 module_param_named(datarouter, enable_multibuffer, bool, 0400);
-MODULE_PARM_DESC(datarouter, "Enable hardware data router support");
+MODULE_PARM_DESC(datarouter, "Enable hardware data router support (default on)");
 
 static int zfcp_qdio_buffers_enqueue(struct qdio_buffer **sbal)
 {