Fix clang warnings in applications

Some fd would be used uninitialized if we goto exit early.
diff --git a/programs/test/ssl_test.c b/programs/test/ssl_test.c
index c8461dc..9c0075f 100644
--- a/programs/test/ssl_test.c
+++ b/programs/test/ssl_test.c
@@ -143,7 +143,7 @@
 static int ssl_test( struct options *opt )
 {
     int ret, i;
-    int client_fd;
+    int client_fd = -1;
     int bytes_to_read;
     int bytes_to_write;
     int offset_to_read = 0;