s390x: remove 's390-squash-mcss' option

This option has been deprecated for two releases; remove it.

Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Acked-by: Halil Pasic <pasic@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
diff --git a/include/hw/s390x/css.h b/include/hw/s390x/css.h
index 35facb4..9da5912 100644
--- a/include/hw/s390x/css.h
+++ b/include/hw/s390x/css.h
@@ -266,11 +266,8 @@
 /**
  * Create a subchannel for the given bus id.
  *
- * If @p bus_id is valid, and @p squash_mcss is true, verify that it is
- * not already in use in the default css, and find a free devno from the
- * default css image for it.
- * If @p bus_id is valid, and @p squash_mcss is false, verify that it is
- * not already in use, and find a free devno for it.
+ * If @p bus_id is valid, verify that it is not already in use, and find a
+ * free devno for it.
  * If @p bus_id is not valid find a free subchannel id and device number
  * across all subchannel sets and all css images starting from the default
  * css image.
@@ -282,7 +279,7 @@
  * The caller becomes owner of the returned subchannel structure and
  * is responsible for unregistering and freeing it.
  */
-SubchDev *css_create_sch(CssDevId bus_id, bool squash_mcss, Error **errp);
+SubchDev *css_create_sch(CssDevId bus_id, Error **errp);
 
 /** Turn on css migration */
 void css_register_vmstate(void);