wifi: brcmfmac: do not cast hidden SSID attribute value to boolean

In 'brcmf_cfg80211_start_ap()', not assume that
NL80211_HIDDEN_SSID_NOT_IN_USE is zero but prefer
an explicit check instead. Compile tested only.

Found by Linux Verification Center (linuxtesting.org) with SVACE.
Signed-off-by: Alexey Berezhok <a@bayrepo.ru>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://msgid.link/20240208085121.2430-1-a@bayrepo.ru

drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c

@@ -5274,7 +5274,7 @@ brcmf_cfg80211_start_ap(struct wiphy *wiphy, struct net_device *ndev,
 					      settings->hidden_ssid);
 		if (err) {
 			bphy_err(drvr, "%s closednet error (%d)\n",
-				 settings->hidden_ssid ?
+				 (settings->hidden_ssid != NL80211_HIDDEN_SSID_NOT_IN_USE) ?
 				 "enabled" : "disabled",
 				 err);
 			goto exit;