[6.0] 095990085 Sync documentation with mgt_main.c

[Dridi Boukelmoune]

commit 0959900854c93656f26fe0dc8a619427d2bb10f3
Author: Dridi Boukelmoune <dridi.boukelmoune at gmail.com>
Date:   Tue Dec 11 18:20:14 2018 +0100

    Sync documentation with mgt_main.c
    
    See `git grep PROXY -- bin/varnishd/mgt/mgt_main.c`.

diff --git a/doc/sphinx/reference/varnishd.rst b/doc/sphinx/reference/varnishd.rst
index de7ee866f..57c657711 100644
--- a/doc/sphinx/reference/varnishd.rst
+++ b/doc/sphinx/reference/varnishd.rst
@@ -57,7 +57,7 @@ Basic options
 
   Name is referenced in logs. If name is not specified, "a0", "a1",
   etc. is used. An additional protocol type can be set for the
-  listening socket with PROTO. Valid protocol types are: HTTP/1
+  listening socket with PROTO. Valid protocol types are: HTTP
   (default), and PROXY.
 
   Multiple listening addresses can be specified by using different