Increase stack for ThreadX demo

Change-Id: I7346b6e57e2579baf44840957e67d870922a5fe8
diff --git a/applications/threadx_demo/main.cpp b/applications/threadx_demo/main.cpp
index cbf1661..5a4a6da 100644
--- a/applications/threadx_demo/main.cpp
+++ b/applications/threadx_demo/main.cpp
@@ -48,7 +48,7 @@
 
 #define MAX_THREAD_NAME_SIZE 128
 
-#define PROCESS_THREAD_STACK_SIZE   (20 * 1024)
+#define PROCESS_THREAD_STACK_SIZE   (32 * 1024)
 #define SENDER_THREAD_STACK_SIZE    (2 * 1024)
 #define PROCESS_THREAD_CONTEXT_SIZE (sizeof(TX_THREAD))
 #define SENDER_THREAD_CONTEXT_SIZE  (sizeof(TX_THREAD))