Add dual role (concurrent) example

This reads HID devices over host and then translates that to ASCII
and sends it over CDC device.

examples/host/hid_to_cdc/Makefile

@@ -0,0 +1,20 @@
+include ../../../tools/top.mk
+include ../../make.mk
+
+INC += \
+	src \
+	$(TOP)/hw \
+
+# Example source
+EXAMPLE_SOURCE += $(wildcard src/*.c)
+SRC_C += $(addprefix $(CURRENT_PATH)/, $(EXAMPLE_SOURCE))
+
+CFLAGS += -Wno-error=cast-align -Wno-error=null-dereference
+
+SRC_C += \
+	src/class/hid/hid_host.c \
+	src/host/hub.c \
+	src/host/usbh.c \
+	src/host/usbh_control.c
+
+include ../../rules.mk