Initial basic work on nice!nano board support.

app/boards/arm/nice_nano/Kconfig.defconfig

@@ -0,0 +1,28 @@
+# Electronut Labs Papyr board configuration
+
+# Copyright (c) 2018 Electronut Labs
+# SPDX-License-Identifier: Apache-2.0
+
+if BOARD_NICE_NANO
+
+config BOARD
+	default "nice_nano"
+
+if USB
+
+config USB_NRFX
+	default y
+
+config USB_DEVICE_STACK
+	default y
+
+endif # USB
+
+config IEEE802154_NRF5
+	default y
+	depends on IEEE802154
+
+config BT_CTLR
+	default BT
+
+endif # BOARD_NICE_NANO