Fix Greentea WiFi test build issues

Author: juhaylinen

TESTS/network/wifi/get_interface.cpp

@@ -19,6 +19,10 @@
     #error [NOT_SUPPORTED] No network interface found for this target.
 #endif
 
+#if !defined(MBED_CONF_APP_WIFI_SECURE_SSID) && !defined(MBED_CONF_APP_WIFI_UNSECURE_SSID)
+    #error [NOT_SUPPORTED] Requires parameters from mbed_app.json
+#endif
+
 #include "mbed.h"
 #include MBED_CONF_APP_HEADER_FILE
 

TESTS/network/wifi/main.cpp

@@ -41,7 +41,6 @@
 #if !defined(MBED_CONF_APP_AP_MAC_UNSECURE)    || \
     !defined(MBED_CONF_APP_MAX_SCAN_SIZE)      || \
     !defined(MBED_CONF_APP_WIFI_CH_UNSECURE)   || \
-    !defined(MBED_CONF_APP_WIFI_PASSWORD)      || \
     !defined(MBED_CONF_APP_WIFI_UNSECURE_SSID)
 #error [NOT_SUPPORTED] Requires parameters from mbed_app.json (for unsecure connections)
 #endif