[asterisk-ss7] Tiny bug with a fix

[Marcelo Pacheco]

asterisk-1.6.2.0-beta2
in chan_dahdi.c, function handle_ss7_debug:

There's a missing ! before strcasecmp. Without it, ss7 set debug works
backwards, with off enabling and on disabling debugging.
        if (linksets[span-1].ss7) {
               if (!strcasecmp(a->argv[3], "on")) {

Regards,

Marcelo Pacheco