wireless/ath6kl: use of module_param requires the inclusion of moduleparam.h

Otheriwse the module.h split up fails like this:

drivers/net/wireless/ath/ath6kl/init.c:27:26: error: expected ')' before 'uint'
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>

drivers/net/wireless/ath/ath6kl/init.c

@@ -15,6 +15,7 @@
  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  */
 
+#include <linux/moduleparam.h>
 #include <linux/of.h>
 #include <linux/mmc/sdio_func.h>
 #include "core.h"