charger: separate UI and HAL access.

Abstract all the HIDL-ness from charger so an AIDL HAL
can later replace the HIDL HAL.

Created libhealthd_charger_ui that is responsible for
UI stuff in charger. Then libhealthd_charger is now the
charger library backed by HIDL HAL.

Bug: 170338625
Bug: 203246116

Test: charger_test

Change-Id: I193bb76afa18b3367f24796ac53b1760650e8683
diff --git a/healthd/charger.cpp b/healthd/charger.cpp
index d03978d..73e04fe 100644
--- a/healthd/charger.cpp
+++ b/healthd/charger.cpp
@@ -15,9 +15,9 @@
  */
 
 #include <android-base/logging.h>
+#include <charger.sysprop.h>
 
-#include "charger.sysprop.h"
-#include "healthd_mode_charger.h"
+#include "healthd_mode_charger_hidl.h"
 #include "healthd_mode_charger_nops.h"
 
 #ifndef CHARGER_FORCE_NO_UI