DFS: Fix range availability check

There's off-by-one in the range availability check - the case of
first_chan_idx + num_chans == num_channels should be allowed (e.g., 0 +
1 == 1, for the case of a single 20 MHz channel).

Signed-off-by: Maital Hahn <maitalm@ti.com>
Signed-off-by: Eliad Peller <eliad@wizery.com>

src/ap/dfs.c

@@ -143,7 +143,7 @@ static int dfs_chan_range_available(struct hostapd_hw_modes *mode,
 	struct hostapd_channel_data *first_chan, *chan;
 	int i;
 
-	if (first_chan_idx + num_chans >= mode->num_channels)
+	if (first_chan_idx + num_chans > mode->num_channels)
 		return 0;
 
 	first_chan = &mode->channels[first_chan_idx];