Fixing device bricking bug

- When loading a garbage image onto the device, the chip hangs
  and refuses to jump to the bootloader and start dfu

Fix
- Check if chip was in locked state and jump to dfu
- Check if watchdog timer fired and jump to dfu

Bootloader/CMakeLists.txt

@@ -20,11 +20,26 @@
 #| You _MUST_ clean the build directory if you change this value
 #|
 set( CHIP
-	"mk20dx128vlf5"    # McHCK    mk20dx128vlf5
-#	"mk20dx256vlh7"    # Kiibohd-dfu
+	"mk20dx128vlf5"    # McHCK       mk20dx128vlf5
+#	"mk20dx256vlh7"    # Kiibohd-dfu mk20dx256vlh7
 )
 
 
+
+###
+# Compiler Selection
+#
+
+#| *** EXPERIMENTAL ***
+#| Stick with gcc unless you know what you're doing
+#| Currently only arm is supported with clang
+set( COMPILER
+	"gcc"	# arm-none-eabi-gcc / avr-gcc - Default
+#	"clang" # arm-none-eabi
+	CACHE STRING "Compiler Type" )
+
+
+
 ###
 # Bootloader Configuration
 #