Initialize last update time to MinValue to account for negative times

[cbrwn]

Rarely, devices' internal times can be negative (not sure the cause), so the initial value of m_lastUpdateTimeInternal being 0 results in no input detected from these devices.

Here I just initialize it to MinValue in the constructor which fixed it for me, but a better fix may exist.

Here's a screenshot of my mouse and keyboard events having negative times (which detected no input) next to my Xbox controller events with positive times, which detected input.

[unity-cla-assistant]

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[jimon]

Hi! We've tried to reproduce the issue with latest Unity versions, and while device event times becoming negative is expected when entering playmode, any new events after that should contain a positive event time in the debugger.

If the issue still persist please create a bug report instead and attach this PR.