rtl8xxxu: Fix sparse warning: cast from restricted __le16

Fix the warning reported by sparse as:
 drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c:4819:17: sparse: sparse: cast from restricted __le16
 drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c:4892:17: sparse: sparse: cast from restricted __le16

Signed-off-by: Chris Chiu <chiu@endlessm.com>
Reported-by: kbuild test robot <lkp@intel.com>
Acked-by: Jes Sorensen <jes@trained-monkey.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200319064341.49500-1-chiu@endlessm.com

drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c

@@ -4816,8 +4816,8 @@ rtl8xxxu_fill_txdesc_v1(struct ieee80211_hw *hw, struct ieee80211_hdr *hdr,
 		rate = tx_rate->hw_value;
 
 	if (rtl8xxxu_debug & RTL8XXXU_DEBUG_TX)
-		dev_info(dev, "%s: TX rate: %d, pkt size %d\n",
-			 __func__, rate, cpu_to_le16(tx_desc->pkt_size));
+		dev_info(dev, "%s: TX rate: %d, pkt size %u\n",
+			 __func__, rate, le16_to_cpu(tx_desc->pkt_size));
 
 	seq_number = IEEE80211_SEQ_TO_SN(le16_to_cpu(hdr->seq_ctrl));
 
@@ -4889,8 +4889,8 @@ rtl8xxxu_fill_txdesc_v2(struct ieee80211_hw *hw, struct ieee80211_hdr *hdr,
 		rate = tx_rate->hw_value;
 
 	if (rtl8xxxu_debug & RTL8XXXU_DEBUG_TX)
-		dev_info(dev, "%s: TX rate: %d, pkt size %d\n",
-			 __func__, rate, cpu_to_le16(tx_desc40->pkt_size));
+		dev_info(dev, "%s: TX rate: %d, pkt size %u\n",
+			 __func__, rate, le16_to_cpu(tx_desc40->pkt_size));
 
 	seq_number = IEEE80211_SEQ_TO_SN(le16_to_cpu(hdr->seq_ctrl));