[S390] zcrypt: Do not start ap poll thread per default

Do not start ap poll thread per default to increase perfomance with
z/VM.

Signed-off-by: Felix Beck <felix.beck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/drivers/s390/crypto/ap_bus.c b/drivers/s390/crypto/ap_bus.c
index 67aaff3..d0c6fd3 100644
--- a/drivers/s390/crypto/ap_bus.c
+++ b/drivers/s390/crypto/ap_bus.c
@@ -61,9 +61,9 @@
 MODULE_PARM_DESC(domain, "domain index for ap devices");
 EXPORT_SYMBOL(ap_domain_index);
 
-static int ap_thread_flag = 1;
+static int ap_thread_flag = 0;
 module_param_named(poll_thread, ap_thread_flag, int, 0000);
-MODULE_PARM_DESC(poll_thread, "Turn on/off poll thread, default is 1 (on).");
+MODULE_PARM_DESC(poll_thread, "Turn on/off poll thread, default is 0 (off).");
 
 static struct device *ap_root_device = NULL;
 static DEFINE_SPINLOCK(ap_device_lock);