qerror.h: Remove QERR defines that are only used once

Just hardcode them in the callers

Cc: Luiz Capitulino <lcapitulino@redhat.com>
Cc: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Cole Robinson <crobinso@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
diff --git a/qobject/json-parser.c b/qobject/json-parser.c
index e7947b3..e46c264 100644
--- a/qobject/json-parser.c
+++ b/qobject/json-parser.c
@@ -110,7 +110,7 @@
         error_free(ctxt->err);
         ctxt->err = NULL;
     }
-    error_set(&ctxt->err, QERR_JSON_PARSE_ERROR, message);
+    error_setg(&ctxt->err, "JSON parse error, %s", message);
 }
 
 /**