Revert " power: wakelock: call __get_wall_to_monotonic() instead of using wall…"

This reverts commit 8704cffe0e8640c53f6238f386ee855b63082cd9.
power: wakelock: use get_xtime_and_monotonic_and_sleep_offset in get_…
…expired_time

Change-Id: I6ebe6b954b2ff328d46898d683650dafb9c4fe74
Signed-off-by: Erik Gilling <konkers@android.com>