ruby: Refactor some Event subclasses to lambdas

Change-Id: I9f47a20a869553515a759d9a29c05f6ce4b42d64
Signed-off-by: Sean Wilson <spwilson2@wisc.edu>
Reviewed-on: https://gem5-review.googlesource.com/3930
Maintainer: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
8 files changed