fix the layout generation target

Makefile

@@ -1,7 +1,7 @@
 # Arduino Make file. Refer to https://github.com/sudar/Arduino-Makefile
 
 BOARD_TAG    = micro
-MONITOR_PORT = /dev/ttyACM*
+MONITOR_PORT = /dev/cu.usbmodem14?1
 ARDUINO_LIBS = 
 
 include build/arduino-mk/Arduino.mk
@@ -10,4 +10,4 @@ astyle:
 	astyle --style=linux ArduinoKeyboard.ino *.h
 
 generate-keymaps:
-	find layout -type f -name \*.conf |xargs perl generate-keymaps.pl < 
+	cd layouts && ( find . -type f |xargs -n 1 -I % sh -c 'perl ../tools/generate_keymaps.pl < % > ../layouts-generated/%.h' )