Add PRINTF_FORMAT for printf wrapper functions

This avoids compiler format-nonliteral warnings ("format string is not a
string literal").

Signed-off-by: Jouni Malinen <j@w1.fi>

src/ap/wpa_auth_i.h

@@ -277,7 +277,8 @@ int wpa_write_rsnxe(struct wpa_auth_config *conf, u8 *buf, size_t len);
 void wpa_auth_logger(struct wpa_authenticator *wpa_auth, const u8 *addr,
 		     logger_level level, const char *txt);
 void wpa_auth_vlogger(struct wpa_authenticator *wpa_auth, const u8 *addr,
-		      logger_level level, const char *fmt, ...);
+		      logger_level level, const char *fmt, ...)
+	PRINTF_FORMAT(4, 5);
 void __wpa_send_eapol(struct wpa_authenticator *wpa_auth,
 		      struct wpa_state_machine *sm, int key_info,
 		      const u8 *key_rsc, const u8 *nonce,

src/eapol_auth/eapol_auth_sm.c

@@ -56,6 +56,7 @@ static void eapol_auth_logger(struct eapol_authenticator *eapol,
 }
 
 
+PRINTF_FORMAT(4, 5)
 static void eapol_auth_vlogger(struct eapol_authenticator *eapol,
 			       const u8 *addr, eapol_logger_level level,
 			       const char *fmt, ...)

src/utils/common.h

@@ -482,7 +482,8 @@ int hexstr2bin(const char *hex, u8 *buf, size_t len);
 void inc_byte_array(u8 *counter, size_t len);
 void buf_shift_right(u8 *buf, size_t len, size_t bits);
 void wpa_get_ntp_timestamp(u8 *buf);
-int wpa_scnprintf(char *buf, size_t size, const char *fmt, ...);
+int wpa_scnprintf(char *buf, size_t size, const char *fmt, ...)
+	PRINTF_FORMAT(3, 4);
 int wpa_snprintf_hex_sep(char *buf, size_t buf_size, const u8 *data, size_t len,
 			 char sep);
 int wpa_snprintf_hex(char *buf, size_t buf_size, const u8 *data, size_t len);