xfree86: loader: add assert() in LoadModule()

There's (remote) chance that the (internal) module name could become
NULL (eg. allocation failure). Even though chances to hit it are very
low, it's still better to have a check here (that doesn't cost us much),
just in case. Assert fail is still better than segfault, since we're
at least getting some hint what might have happened.

Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>

hw/xfree86/loader/loadmod.c

@@ -702,6 +702,8 @@ LoadModule(const char *module, void *options, const XF86ModReqInfo *modreq,
     if (!strcmp(m, "vbe"))
         m = name = strdup("int10");
 
+    assert(m);
+
     for (cim = compiled_in_modules; *cim; cim++)
         if (!strcmp(m, *cim)) {
             LogMessageVerb(X_INFO, 3, "Module \"%s\" already built-in\n", m);