ath10k: add might_sleep() to ath10k_wmi_cmd_send()

ath10k_wmi_cmd_send() will now sleep if there are no credits available.
To make it easier to catch callers in atomic context add might_sleep()
to the function.

Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>
diff --git a/drivers/net/wireless/ath/ath10k/wmi.c b/drivers/net/wireless/ath/ath10k/wmi.c
index d1e513e..77238af 100644
--- a/drivers/net/wireless/ath/ath10k/wmi.c
+++ b/drivers/net/wireless/ath/ath10k/wmi.c
@@ -613,6 +613,8 @@
 {
 	int ret = -EOPNOTSUPP;
 
+	might_sleep();
+
 	if (cmd_id == WMI_CMD_UNSUPPORTED) {
 		ath10k_warn("wmi command %d is not supported by firmware\n",
 			    cmd_id);