hostap: fix sparse warnings

Rewrite AID calculation in handle_pspoll() to avoid truncating bits.
Make hostap_80211_header_parse() static, don't export it.  Avoid
shadowing variables.

Signed-off-by: Pavel Roskin <proski@gnu.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/hostap/hostap_ap.c b/drivers/net/wireless/hostap/hostap_ap.c
index 0acd958..ab981af 100644
--- a/drivers/net/wireless/hostap/hostap_ap.c
+++ b/drivers/net/wireless/hostap/hostap_ap.c
@@ -1930,7 +1930,7 @@
 		PDEBUG(DEBUG_PS, "   PSPOLL and AID[15:14] not set\n");
 		return;
 	}
-	aid &= ~BIT(15) & ~BIT(14);
+	aid &= ~(BIT(15) | BIT(14));
 	if (aid == 0 || aid > MAX_AID_TABLE_SIZE) {
 		PDEBUG(DEBUG_PS, "   invalid aid=%d\n", aid);
 		return;