[gxml] Set required Vala version to 0.35.6.7

[Daniel Espinosa Ortiz <despinosa src gnome org>]

commit 9f34bcbdddf16b47434c25089edd57eb444e9414
Author: Daniel Espinosa <esodan gmail com>
Date:   Thu Mar 2 15:24:54 2017 -0600

    Set required Vala version to 0.35.6.7

 configure.ac |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/configure.ac b/configure.ac
index 8da1bcd..419dd01 100644
--- a/configure.ac
+++ b/configure.ac
@@ -115,7 +115,7 @@ AC_SUBST(GXML_LOCALEDIR)
 # TODO: what do we do about libvala's versioning?  set it back to -0.18 and see what happens when we 
upgraded from Fedora 18 to 19
 
 GLIB_REQUIRED=2.32.0
-VALA_REQUIRED=0.34.0
+VALA_REQUIRED=0.35.6.7
 LIBVALA_REQUIRED=0.34
 GEE_REQUIRED=0.18.0
 LIBXML_REQUIRED=2.7