test st7735 on lpc1768 with mbed v5. bug with spi frequency...

Revision:
1:121b61eeffe7
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mbed_app.json	Wed Apr 08 14:52:09 2020 +0000
@@ -0,0 +1,7 @@
+{
+    "target_overrides": {
+        "*": {
+            "target.components_add": ["SD"]
+        }
+    }
+}