Update README.md

Samples/HelloBlinkyBackground/CS/README.md

@@ -1,6 +1,6 @@
 # "Hello, blinky!" background service
 
-We'll create a simple Blinky app and connect a LED to your Windows IoT Core device (Raspberry Pi 2 or 3, MinnowBoard Max or DragonBoard).  Be aware that the GPIO APIs are
+We'll create a simple Blinky app and connect a LED to your Windows IoT Core device (Raspberry Pi 2 or 3, Up Squared or DragonBoard).  Be aware that the GPIO APIs are
 only available on Windows IoT Core, so this sample cannot run on your desktop.
 
 ## Headless mode