buildroot

nginx-dav-ext: depends on BR2_PACKAGE_NGINX_HTTP_DAV_MODULE

This package adds missing WebDAB commands to NGINX. So, it makes sense
iff Nginx is compiled with the WebDAV support.

Fixes:

  http://autobuild.buildroot.net/results/6e997faf553dc70d0aa1ee811fd669650349cba2/

Signed-off-by: Johan Oudinet <johan.oudinet@gmail.com>
[Thomas: fix indentation, add autobuilder reference.]
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>