staging: rtl8192e: Use standard function in rtllib_rx_check_duplicate()

Use standard function ieee80211_is_beacon() to avoid proprietary code and
to increase readability.
Signed-off-by: Philipp Hortmann <philipp.g.hortmann@gmail.com>
Link: https://lore.kernel.org/r/b74b6ef5e266504b9e3d84495bcd8fe4978b4ded.1694546300.git.philipp.g.hortmann@gmail.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/rtl8192e/rtllib_rx.c

@@ -904,11 +904,9 @@ static int rtllib_rx_check_duplicate(struct rtllib_device *ieee,
 {
 	struct rtllib_hdr_4addr *hdr = (struct rtllib_hdr_4addr *)skb->data;
 	u16 fc, sc;
-	u8 frag, type, stype;
+	u8 frag;
 
 	fc = le16_to_cpu(hdr->frame_ctl);
-	type = WLAN_FC_GET_TYPE(fc);
-	stype = WLAN_FC_GET_STYPE(fc);
 	sc = le16_to_cpu(hdr->seq_ctl);
 	frag = WLAN_GET_SEQ_FRAG(sc);
 
@@ -916,8 +914,7 @@ static int rtllib_rx_check_duplicate(struct rtllib_device *ieee,
 		!ieee->current_network.qos_data.active ||
 		!IsDataFrame(skb->data) ||
 		IsLegacyDataFrame(skb->data)) {
-		if (!((type == RTLLIB_FTYPE_MGMT) &&
-		      (stype == RTLLIB_STYPE_BEACON))) {
+		if (!ieee80211_is_beacon(hdr->frame_ctl)) {
 			if (is_duplicate_packet(ieee, hdr))
 				return -1;
 		}