ath: Add and use pr_fmt, convert printks to pr_<level>

Use a more current logging style.
Make sure all output is prefixed appropriately.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

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

@@ -15,6 +15,8 @@
  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  */
 
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
 #include "core.h"
 #include "hif-ops.h"
 #include "cfg80211.h"