[6.5] f3614262f Bump the VRT major version

[Martin Blix Grydeland]

commit f3614262f130aedaae4f8ed975b3801607ddce5d
Author: Martin Blix Grydeland <martin at varnish-software.com>
Date:   Wed Sep 23 11:46:09 2020 +0200

    Bump the VRT major version
    
    In the Varnish Cache 6.5.0 release we forgot to bump the VRT major
    version. Do it now.

diff --git a/include/vrt.h b/include/vrt.h
index c4858cd8b..5b16c6261 100644
--- a/include/vrt.h
+++ b/include/vrt.h
@@ -166,7 +166,7 @@
  *	vrt_acl type added
  */
 
-#define VRT_MAJOR_VERSION	11U
+#define VRT_MAJOR_VERSION	12U
 
 #define VRT_MINOR_VERSION	0U