cmd/compile: failed "no write barrier" check compiling "runtime" in TestAbstractOriginSanity

[adonovan]

See https://go.dev/cl//581215: changes to runtime.throw cause a particular linker test using stronger inlining to fail the "write barrier" static reachability check.

[gopherbot]

Change https://go.dev/cl/584616 mentions this issue: runtime: add workaround to "throw" pending resolution of issue #67274

[gopherbot]

Change https://go.dev/cl/584617 mentions this issue: runtime: make convTstring write barrier unreachable from throw