ssdptax: discover all URLs

ssdptax was only checking the first URL it found through
SSDP. However most devices provide more than one URL
for different functions, and sometimes the friendlyName
and model information is different for the different URLs.
Check all of them, and print all of the different information
we find.

GSAFSJ1412D0117# /tmp/ssdptax
ssdp 40:16:7e:a3:0c:f0 ASUS WPS Router;ASUSTeK Corporation WPS Router
ssdp 40:16:7e:a3:0c:f0 RT-AC68U;ASUSTeK Computer Inc. Windows Media Connect compatible
ssdp 5c:f6:dc:8e:44:a8 [TV]Samsung LED60;Samsung Electronics UN60F6300
GSAFSJ1412D0117#

Redo the unit test: before, we buried test data in the binary.
This worked but didn't exercise the communication path with minissdpd
nor the curl code to fetch the URLs. Instead supply a test server which
both impersonates minissdpd to supply the list of one SSDP device and also
serves as the web server to fetch XML from that client.

Change-Id: If757cd69c916fe15b2d1778d93e1b5513f61f6d8
3 files changed