ath6kl: Fix typo in htc mbox debug print msg

Add missing ZERO (x%x to 0x%x) in the format specifier
while printing hex value in htc module.
Signed-off-by: NRaja Mani <rmani@qca.qualcomm.com>
Signed-off-by: NKalle Valo <kvalo@qca.qualcomm.com>

drivers/net/wireless/ath/ath6kl/htc_mbox.c

@@ -1309,7 +1309,7 @@ static int ath6kl_htc_rx_packet(struct htc_target *target,
 	}
 
 	ath6kl_dbg(ATH6KL_DBG_HTC,
-		   "htc rx 0x%p hdr x%x len %d mbox 0x%x\n",
+		   "htc rx 0x%p hdr 0x%x len %d mbox 0x%x\n",
 		   packet, packet->info.rx.exp_hdr,
 		   padded_len, dev->ar->mbox_info.htc_addr);