hostap: convert usage of net/ieee80211.h to linux/ieee80211.h

So that net/ieee80211.h can be made private to ipw2x00 in a follow-up.

Signed-off-by: Dan Williams <dcbw@redhat.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/hostap/hostap_info.c b/drivers/net/wireless/hostap/hostap_info.c
index 99b4cf4..6fa14a4 100644
--- a/drivers/net/wireless/hostap/hostap_info.c
+++ b/drivers/net/wireless/hostap/hostap_info.c
@@ -1,5 +1,6 @@
 /* Host AP driver Info Frame processing (part of hostap.o module) */
 
+#include <linux/if_arp.h>
 #include "hostap_wlan.h"
 #include "hostap.h"
 #include "hostap_ap.h"