[chip dv xcelium] Add a dedicated regression target for Xcelium
[chip dv xcelium] Add a dedicated regression target for Xcelium

THis adds a dedicated mini regression target for Xcelium that can
be invoked in presubmit CI.

Signed-off-by: Srikrishna Iyer <2803d640feace36379942447842f26c7747b4dc3@google.com>

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