cleanup migrated XPointer module to the new error mechanism Daniel

* xpath.c: cleanup
* xpointer.c include/libxml/xmlerror.h: migrated XPointer module
  to the new error mechanism
Daniel
diff --git a/xpath.c b/xpath.c
index 8008491..1775c2e 100644
--- a/xpath.c
+++ b/xpath.c
@@ -289,7 +289,7 @@
     ctxt->context->lastError.domain = XML_FROM_XPATH;
     ctxt->context->lastError.code = error + XML_XPATH_EXPRESSION_OK -
                            XPATH_EXPRESSION_OK;
-    ctxt->context->lastError.level = XML_ERR_FATAL;
+    ctxt->context->lastError.level = XML_ERR_ERROR;
     ctxt->context->lastError.str1 = (char *) xmlStrdup(ctxt->base);
     ctxt->context->lastError.int1 = ctxt->cur - ctxt->base;
     ctxt->context->lastError.node = ctxt->context->debugNode;