build: remove support for s390 (but not s390x)
Upstream V8 removed support for s390 earlier this year and it's known to no longer build. Remove the support from our build scripts.
Do not update/delete: Banner broadcast message test data
Do not update/delete: Notification broadcast message test data
Upstream V8 removed support for s390 earlier this year and it's known to no longer build. Remove the support from our build scripts.