docs: reST-ify vhost-user documentation

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20190315180735.13096-1-marcandre.lureau@redhat.com>
Reviewed-by: Jens Freimann <jfreimann@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
diff --git a/MAINTAINERS b/MAINTAINERS
index 9424a49..a6948eb 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -1484,7 +1484,7 @@
 S: Supported
 F: hw/*/*vhost*
 F: docs/interop/vhost-user.json
-F: docs/interop/vhost-user.txt
+F: docs/interop/vhost-user.rst
 F: contrib/vhost-user-*/
 F: backends/vhost-user.c
 F: include/sysemu/vhost-user-backend.h