Fix entry.c for STM32L4. Now, USB works.

entry.c

@@ -54,7 +54,9 @@ main (int argc, const char *argv[])
  * Avoid medium density specific code and prepare for high density
  * device, too.
  */
+#if !defined(MCU_STM32L4)
 #define STM32F10X_HD
+#endif
 #else
 #if defined (MCU_KINETIS_L)
 #include "mcu/clk_gpio_init-mkl27z.c"

example-cdc/usb-cdc.c

@@ -2,6 +2,7 @@
 #include <stdlib.h>
 #include <chopstx.h>
 #include <string.h>
+#include "board.h"
 #include "usb_lld.h"
 #include "tty.h"