hwsim: make testmode_cmd static

sparse correctly complains about this, no reason
for it not to be static.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/mac80211_hwsim.c b/drivers/net/wireless/mac80211_hwsim.c
index 6ac8565..4befa48 100644
--- a/drivers/net/wireless/mac80211_hwsim.c
+++ b/drivers/net/wireless/mac80211_hwsim.c
@@ -729,7 +729,8 @@
 
 static int hwsim_fops_ps_write(void *dat, u64 val);
 
-int mac80211_hwsim_testmode_cmd(struct ieee80211_hw *hw, void *data, int len)
+static int mac80211_hwsim_testmode_cmd(struct ieee80211_hw *hw,
+				       void *data, int len)
 {
 	struct mac80211_hwsim_data *hwsim = hw->priv;
 	struct nlattr *tb[HWSIM_TM_ATTR_MAX + 1];