Update to latest SoftwareSerial for Delegate fix

earlephilhower · earlephilhower · commit 89cacef28e79 · 2020-02-28T09:28:20.000-08:00
diff --git a/libraries/SoftwareSerial b/libraries/SoftwareSerial
@@ -1 +1 @@
-Subproject commit 3df8cdd5e00e72554f1c0ae00e8e7a2a3cfb169b
+Subproject commit 6153c20e71e61f1243dd5780dcd64fb18b6890f7
