In a complete lack of foresight on my part, my previous commit broke

the assumption that ath_softc doesn't change size based on build time
configuration.

I picked up on this because suddenly radar stuff didn't work; and
although the ath_dfs code was setting sc_dodfs=1, the main ath driver
saw sc_dodfs=0.

So for now, include opt_ath.h in driver source files.  This seems like
the sane thing to do anyway.

I'll have to do a pass over the code at some later stage and turn
the radiotap TX/RX structs into malloc'ed memory, rather than in-line
inside of ath_softc.  I'd rather like to keep ath_softc the same
layout regardless of configuration parameters.

Pointy hat to: 	adrian

sys/dev/ath/ath_dfs/null/dfs_null.c

@@ -34,6 +34,7 @@ __FBSDID("$FreeBSD$");
 /*
  * This implements an empty DFS module.
  */
+#include "opt_ath.h"
 #include "opt_inet.h"
 #include "opt_wlan.h"
 

sys/dev/ath/ath_rate/amrr/amrr.c

@@ -45,6 +45,7 @@ __FBSDID("$FreeBSD$");
  * "IEEE 802.11 Rate Adaptation: A Practical Approach" by
  *    Mathieu Lacage, Hossein Manshaei, Thierry Turletti
  */
+#include "opt_ath.h"
 #include "opt_inet.h"
 #include "opt_wlan.h"
 

sys/dev/ath/ath_rate/onoe/onoe.c

@@ -33,6 +33,7 @@ __FBSDID("$FreeBSD$");
 /*
  * Atsushi Onoe's rate control algorithm.
  */
+#include "opt_ath.h"
 #include "opt_inet.h"
 #include "opt_wlan.h"
 

sys/dev/ath/ath_rate/sample/sample.c

@@ -41,6 +41,7 @@ __FBSDID("$FreeBSD$");
 /*
  * John Bicket's SampleRate control algorithm.
  */
+#include "opt_ath.h"
 #include "opt_inet.h"
 #include "opt_wlan.h"
 #include "opt_ah.h"

sys/dev/ath/if_ath_ahb.c

@@ -35,6 +35,8 @@ __FBSDID("$FreeBSD$");
  * AHB bus front-end for the Atheros Wireless LAN controller driver.
  */
 
+#include "opt_ath.h"
+
 #include <sys/param.h>
 #include <sys/systm.h> 
 #include <sys/module.h>