brcmfmac: use atomic_t for statistic counter in struct brcmf_bus

The statistic counter is used in common layer and in the bus layer
in different thread contexts so change to use atomic operations.
Reviewed-by: Hante Meuleman <hante.meuleman@broadcom.com>
Reviewed-by: Pieter-Paul Giesberts <pieter-paul.giesberts@broadcom.com>
Reviewed-by: Franky Lin <franky.lin@broadcom.com>
Signed-off-by: Arend van Spriel <arend.vanspriel@broadcom.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

drivers/net/wireless/broadcom/brcm80211/brcmfmac/bus.h

@@ -138,7 +138,7 @@ struct brcmf_bus {
 	struct brcmf_pub *drvr;
 	enum brcmf_bus_state state;
 	uint maxctl;
-	unsigned long tx_realloc;
+	atomic_t tx_realloc;
 	u32 chip;
 	u32 chiprev;
 	bool always_use_fws_queue;

drivers/net/wireless/broadcom/brcm80211/brcmfmac/sdio.c

@@ -2046,7 +2046,7 @@ static int brcmf_sdio_txpkt_hdalign(struct brcmf_sdio *bus, struct sk_buff *pkt)
 	head_pad = ((unsigned long)dat_buf % bus->head_align);
 	if (head_pad) {
 		if (skb_headroom(pkt) < head_pad) {
-			bus->sdiodev->bus_if->tx_realloc++;
+			atomic_inc(&bus->sdiodev->bus_if->tx_realloc);
 			head_pad = 0;
 			if (skb_cow(pkt, head_pad))
 				return -ENOMEM;