incidentd: Updating process state enum.

It's fine to rearrange and update right now since the protos aren't
being used yet. In the future, we should just update the mapping
function.

Bug: 65750826
Test: $ cts-tradefed run cts-dev --module CtsIncidentHostTestCases --test com.android.server.cts.PowerIncidentTest
Change-Id: Ia5e44ec74009a68e06d74e0cfb4a4c83b1bcb58a