power: Update DT2W_PATH

* TARGET_TAP_TO_WAKE_NODE is defined in if condition. But in DT2W_PATH, TARGET_DT2W_PATH is defined. Why?
* Use same flag for both, otherwise we need to define two flags for the dt2w path.
* Use TARGET_TAP_TO_WAKE_NODE instead of TARGET_DT2W_PATH, for similarity with qcom powerHAL.

Change-Id: I87cbdc3f2aa1a3f9f6509580f2c1f001129a0fda
(cherry picked from commit 987dcca8)