Error out if user configures SQLite DB without CONFIG_SQLITE

This should make it more obvious to users that they have a fatal
configuration problem in hostapd authentication server.

Signed-off-by: Ben Greear <greearb@candelatech.com>
diff --git a/hostapd/config_file.c b/hostapd/config_file.c
index cae9fd3..82b08f9 100644
--- a/hostapd/config_file.c
+++ b/hostapd/config_file.c
@@ -222,9 +222,15 @@
 		return 0;
 
 	if (os_strncmp(fname, "sqlite:", 7) == 0) {
+#ifdef CONFIG_SQLITE
 		os_free(conf->eap_user_sqlite);
 		conf->eap_user_sqlite = os_strdup(fname + 7);
 		return 0;
+#else /* CONFIG_SQLITE */
+		wpa_printf(MSG_ERROR,
+			   "EAP user file in SQLite DB, but CONFIG_SQLITE was not enabled in the build.");
+		return -1;
+#endif /* CONFIG_SQLITE */
 	}
 
 	f = fopen(fname, "r");