lib-httpd: extend module location auto-detection
Although it is possible to manually set LIB_HTTPD_PATH and
LIB_HTTPD_MODULE_PATH to point at the location of `httpd` and its
modules, doing so is cumbersome and easily forgotten. To address this,
0d344738dc (t/lib-http.sh: Restructure finding of default httpd
location, 2010-01-02) enhanced lib-httpd.sh to automatically detect the
location of `httpd` and its modules in order to facilitate out-of-the-
box testing on a wider range of platforms. Follow that lead by further
enhancing it to automatically detect the `httpd` modules on Void Linux,
as well.
Signed-off-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>