StartHidlServices wait for StartSensorService.

Otherwise, StartHidlServices waits for more than a second
while holding a lock, delaying window manager.

Test: boots
Test: SystemServerTiming_StartWindowManagerService does not regress
Logcat shows:
SystemServerTimingAsync: StartSensorService took to complete: 55ms
SystemServerTiming: StartWindowManagerService took to complete: 81ms
SystemServerTiming: StartHidlServices took to complete: 1ms

Test: lshal shows android.frameworks.sensorservice@1.0::ISensorManager

Bug: 36389997
Change-Id: Iab5cf0ad7059cf9736cc7db0567dff51cc427b58