build: remove Linux DVB test fragment

Most of the DVB test fragment was added in 2e399f39 by someone who
wasn't asked for LGPL relicensing permission. Thus remove it. (For some
weird reason, the configure check wasn't even for the later added actual
DVB code.)

Since DVB is disabled by default, this isn't too bad. But if someone
enables it, and the system doesn't support it, he will receive a weird
compilation error. That has to be good enough, until maybe someone adds
a new check.

waftools/fragments/dvb.c

@@ -1,12 +0,0 @@
-#include <poll.h>
-#include <sys/ioctl.h>
-#include <stdio.h>
-#include <time.h>
-#include <unistd.h>
-#include <linux/dvb/dmx.h>
-#include <linux/dvb/frontend.h>
-#include <linux/dvb/video.h>
-#include <linux/dvb/audio.h>
-#include <linux/dvb/version.h>
-fe_bandwidth_t t;
-int main(void) {return 0;}

wscript

@@ -840,7 +840,7 @@ radio_and_tv_features = [
     } , {
         'name': '--dvbin',
         'desc': 'DVB input module',
-        'func': check_cc(fragment=load_fragment('dvb.c')),
+        'func': check_true,
         'default': 'disable',
     }
 ]