mos(4) broadcast fix

[Stefan Sperling]

mos(4) doesn't set IFF_BROADCAST, which prevents hostapd(8) from using it.
hostapd tries a SIOCGIFBRDADDR ioctl which fails with EINVAL in netinet/in.c:

        case SIOCGIFBRDADDR:
                if ((ifp->if_flags & IFF_BROADCAST) == 0)
                        return (EINVAL);

Index: if_mos.c
===================================================================
RCS file: /cvs/src/sys/dev/usb/if_mos.c,v
retrieving revision 1.13
diff -u -p -r1.13 if_mos.c
--- if_mos.c    25 Jan 2011 20:03:35 -0000      1.13
+++ if_mos.c    20 Feb 2011 21:46:53 -0000
@@ -719,7 +719,7 @@ mos_attach(struct device *parent, struct
        /* Initialize interface info.*/
        ifp = GET_IFP(sc);
        ifp->if_softc = sc;
-       ifp->if_flags = IFF_SIMPLEX | IFF_MULTICAST;
+       ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
        ifp->if_ioctl = mos_ioctl;
        ifp->if_start = mos_start;
        ifp->if_watchdog = mos_watchdog;