mwifiex: use ktime_get_real for timestamping

The mwifiex_11n_aggregate_pkt() function creates a ktime_t from
a timeval returned by do_gettimeofday, which is slow and causes
an overflow in 2038 on 32-bit architectures.

This solves both problems by using the appropriate ktime_get_real()
function.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Amitkumar Karwar <akarwar@marvell.com>
Cc: Nishant Sarmukadam <nishants@marvell.com>
Cc: Kalle Valo <kvalo@codeaurora.org>
Cc: linux-wireless@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/wireless/mwifiex/11n_aggr.c

@@ -173,7 +173,6 @@ mwifiex_11n_aggregate_pkt(struct mwifiex_private *priv,
 	int pad = 0, aggr_num = 0, ret;
 	struct mwifiex_tx_param tx_param;
 	struct txpd *ptx_pd = NULL;
-	struct timeval tv;
 	int headroom = adapter->iface_type == MWIFIEX_USB ? 0 : INTF_HEADER_LEN;
 
 	skb_src = skb_peek(&pra_list->skb_head);
@@ -203,8 +202,7 @@ mwifiex_11n_aggregate_pkt(struct mwifiex_private *priv,
 	tx_info_aggr->flags |= MWIFIEX_BUF_FLAG_AGGR_PKT;
 	skb_aggr->priority = skb_src->priority;
 
-	do_gettimeofday(&tv);
-	skb_aggr->tstamp = timeval_to_ktime(tv);
+	skb_aggr->tstamp = ktime_get_real();
 
 	do {
 		/* Check if AMSDU can accommodate this MSDU */