power: Refactor TARGET_TAP_TO_WAKE_NODE

Add TARGET_POWER_SET_FEATURE_LIB, since other devices
are not simply writing a 0/1 to a device node.
TARGET_TAP_TO_WAKE_NODE is still valid and both
TARGET_TAP_TO_WAKE_NODE and TARGET_POWER_SET_FEATURE_LIB are
allowed to coexist. (Currently set_feature only has double tap
to wake, but it may be extended in future)

Change-Id: I5c6204fd38a6fbe48e8aac49843bfa047c4b6436
diff --git a/power-feature.h b/power-feature.h
new file mode 100644
index 0000000..abf0d4e
--- /dev/null
+++ b/power-feature.h
@@ -0,0 +1,33 @@
+/*
+ * Copyright (C) 2015 The CyanogenMod Project
+ * Copyright (C) 2019 The LineageOS Project
+ *
+ * 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.
+ */
+
+#ifndef _QCOM_POWER_FEATURE_H
+#define _QCOM_POWER_FEATURE_H
+
+#include <hardware/power.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+void set_device_specific_feature(feature_t feature, int state);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif