In xmlSchemaAssembleByXSI() the return value of xmlSchemaGetMetaAttrInfo()

* xmlschemas.c: In xmlSchemaAssembleByXSI() the return value
  of xmlSchemaGetMetaAttrInfo() was not assigned to anything;
  this caused XSI-driven-dynamic schema acquisition to fail
  with @noNamespaceSchemaLocation (reported by Julien Lamy
  on the mailing list).
diff --git a/xmlschemas.c b/xmlschemas.c
index 87a0540..f850458 100644
--- a/xmlschemas.c
+++ b/xmlschemas.c
@@ -21423,7 +21423,7 @@
     iattr = xmlSchemaGetMetaAttrInfo(vctxt,
 	XML_SCHEMA_ATTR_INFO_META_XSI_SCHEMA_LOC);
     if (iattr == NULL)
-	xmlSchemaGetMetaAttrInfo(vctxt,
+	iattr = xmlSchemaGetMetaAttrInfo(vctxt,
 	XML_SCHEMA_ATTR_INFO_META_XSI_NO_NS_SCHEMA_LOC);
     if (iattr == NULL)
 	return (0);