lighttpd: include mod_h2 in base package

lighttpd: include mod_h2 in base package

The next version of lighttpd will move HTTP/2 support from the lighttpd
base executable into a separate module: mod_h2

Include patch to do so now, and update packaging to handle it.

HTTP/2 support is enabled by default since lighttpd 1.4.59, but if
HTTP/2 support is explicitly disabled in the configuration, then mod_h2
will not be loaded, thereby reducing lighttpd memory use.

Signed-off-by: Glenn Strauss <gstrauss@gluelogic.com>
(cherry picked from commit f4152fccadc021b016b341526ddf83ddcf593ca1)