disk/lvm: Do not allow a LV to be it's own segment's node's LV

This prevents infinite recursion in the diskfilter verification code.

Signed-off-by: Daniel Axtens <dja@axtens.net>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>

grub-core/disk/lvm.c

@@ -981,10 +981,14 @@ grub_lvm_detect (grub_disk_t disk,
 		    }
 		if (lv1->segments[i].nodes[j].pv == NULL)
 		  for (lv2 = vg->lvs; lv2; lv2 = lv2->next)
+		    {
+		      if (lv1 == lv2)
+		        continue;
 		      if (grub_strcmp (lv2->name,
 				       lv1->segments[i].nodes[j].name) == 0)
 			lv1->segments[i].nodes[j].lv = lv2;
 		    }
+	      }
 	
       }