drivers/nble: Introduce basic skeleton

Introduce the basic skeleton for NBLE, which is the Bluetooth LE API
implementation targeting a custom firmware running on Nordic
Semiconductor nRF51 chips.

Change-Id: I1ce69d6ee0205e71f6bd8d256d9233c93d2cde41
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>

drivers/nble/Kconfig

@@ -0,0 +1,50 @@
+# Kconfig - NBLE configuration options
+
+#
+# Copyright (c) 2016 Intel Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+# These BLUETOOTH_* dependencies are redefined here since we can't use
+# net/bluetooth/KConfig (which depend on CONFIG_BLUETOOTH)
+#
+config BLUETOOTH_PERIPHERAL
+	bool
+	default n
+
+config BLUETOOTH_CENTRAL
+	bool
+	default n
+
+config BLUETOOTH_GATT_CLIENT
+	bool
+	default n
+
+config BLUETOOTH_SMP
+	bool
+	default n
+
+config NBLE
+	bool "Support for custom Nordic Semiconductor BLE protocol"
+	default n
+	depends on !BLUETOOTH
+	select BLUETOOTH_PERIPHERAL
+	select BLUETOOTH_CENTRAL
+	select BLUETOOTH_GATT_CLIENT
+	select BLUETOOTH_SMP
+	help
+	  Enables support for using Nordic Semicondutor nRF51 Bluetooth
+	  LE chips with a custom firmware. The API for this is a subset of
+	  the normal Bluetooth API (include/bluetooth/*.h). This driver can
+	  only be enabled if CONFIG_BLUETOOTH has not been enabled.