xpath BUGFIX child axis does not include siblings

Fixes #1938
diff --git a/src/xpath.c b/src/xpath.c
index 1136bad..919ab23 100644
--- a/src/xpath.c
+++ b/src/xpath.c
@@ -6584,7 +6584,7 @@
             }
 
             assert(scnode);
-            if (!lysc_data_parent(scnode)) {
+            if ((axis != LYXP_AXIS_CHILD) && !lysc_data_parent(scnode)) {
                 /* iterating over top-level nodes, find next */
                 while (lysc_data_parent(*iter)) {
                     *iter = lysc_data_parent(*iter);