[S390] iucv cr0 enablement bit

Do not set the cr0 enablement bit for iucv by default in head[31|64].S,
move the enablement to iucv_init in the iucv base layer.
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

arch/s390/kernel/head31.S

@@ -45,7 +45,7 @@ ENTRY(startup_continue)
 					# virtual and never return ...
 	.align	8
 .Lentry:.long	0x00080000,0x80000000 + _stext
-.Lctl:	.long	0x04b50002		# cr0: various things
+.Lctl:	.long	0x04b50000		# cr0: various things
 	.long	0			# cr1: primary space segment table
 	.long	.Lduct			# cr2: dispatchable unit control table
 	.long	0			# cr3: instruction authorization

arch/s390/kernel/head64.S

@@ -46,7 +46,7 @@ ENTRY(startup_continue)
 	.align	16
 .LPG1:
 .Lentry:.quad	0x0000000180000000,_stext
-.Lctl:	.quad	0x04350002		# cr0: various things
+.Lctl:	.quad	0x04350000		# cr0: various things
 	.quad	0			# cr1: primary space segment table
 	.quad	.Lduct			# cr2: dispatchable unit control table
 	.quad	0			# cr3: instruction authorization

net/iucv/iucv.c

@@ -1988,12 +1988,13 @@ static int __init iucv_init(void)
 		rc = -EPROTONOSUPPORT;
 		goto out;
 	}
+	ctl_set_bit(0, 1);
 	rc = iucv_query_maxconn();
 	if (rc)
-		goto out;
+		goto out_ctl;
 	rc = register_external_interrupt(0x4000, iucv_external_interrupt);
 	if (rc)
-		goto out;
+		goto out_ctl;
 	iucv_root = root_device_register("iucv");
 	if (IS_ERR(iucv_root)) {
 		rc = PTR_ERR(iucv_root);
@@ -2055,6 +2056,8 @@ static int __init iucv_init(void)
 	root_device_unregister(iucv_root);
 out_int:
 	unregister_external_interrupt(0x4000, iucv_external_interrupt);
+out_ctl:
+	ctl_clear_bit(0, 1);
 out:
 	return rc;
 }