patch 8.1.0167: lock flag in new dictitem is reset in many places

Problem:    Lock flag in new dictitem is reset in many places.
Solution:   Always reset the lock flag.
diff --git a/src/if_perl.xs b/src/if_perl.xs
index 7b45033..40955eb 100644
--- a/src/if_perl.xs
+++ b/src/if_perl.xs
@@ -1200,10 +1200,8 @@
 
 		    if ((item = dictitem_alloc((char_u *)key)) == NULL)
 			break;
-
-		    item->di_tv.v_type		= VAR_NUMBER;
-		    item->di_tv.v_lock		= 0;
-		    item->di_tv.vval.v_number	= 0;
+		    item->di_tv.v_type = VAR_NUMBER;
+		    item->di_tv.vval.v_number = 0;
 
 		    if (dict_add(dict, item) == FAIL) {
 			dictitem_free(item);