astyle ignore: add pithy from tests

0xc0170 · 0xc0170 · commit 56eea3f58226 · 2018-10-25T09:58:17.000+01:00
External code thus ignored
diff --git a/.astyleignore b/.astyleignore
@@ -14,5 +14,6 @@ hal/storage_abstraction
 FEATURE_NANOSTACK/coap-service
 FEATURE_NANOSTACK/sal-stack-nanostack
 rtos/TARGET_CORTEX/rtx5
+TESTS/mbed_hal/trng/pithy
 targets
 tools
