cmd/link: add new linknames to blocked linkname list
Update the blocklist with new linknames added in Go 1.26.
Some goroutine leak profile symbols were manually added but they
did not match the actual symbol names. Corrected.
runtime.freegc is not itself push-linknamed, so there is no need
to explicitly add it to blocklist. Keep the test, to ensure one
cannot linkname-pull freegc.
Change-Id: Ie5fd6bc191e9afa164fa79055cc39e6fa9ed4c7f
Reviewed-on: https://go-review.googlesource.com/c/go/+/729720
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: David Chase <drchase@google.com>