Update README.md

Author: deanm1278

README.md

@@ -2,7 +2,6 @@
 
 ## Known Issues:
 * gcc optimizations must be off for sketches to work consistently. We are working to track this down.
-* board must be in bootloader mode to upload sketches. This is related to the above issue and hopefully will be fixed soon.
 * AREF must be tied to 3.3V for dac to work. This is a bug in the SAMD51 silicon.
 
 This repository contains the source code and configuration files of the Arduino Core