x/build,cmd/go: `unexpected stale targets` on `linux-loong64-3a5000`

[gopherbot]

#!watchflakes
post <- builder == "linux-loong64-3a5000" && log ~ `unexpected stale targets`

Issue created automatically to collect these failures.

Example (log):

go tool dist: unexpected stale targets reported by /tmp/workdir-host-linux-loong64-3a5000/go/pkg/tool/linux_loong64/go_bootstrap list -gcflags="" -ldflags="" for [cmd] (consider rerunning with GOMAXPROCS=1 GODEBUG=gocachehash=1):
	STALE cmd/pprof: stale dependency: cmd/vendor/github.com/google/pprof/internal/driver
	STALE cmd/vendor/github.com/google/pprof/driver: stale dependency: cmd/vendor/github.com/google/pprof/internal/driver
	STALE cmd/vendor/github.com/google/pprof/internal/driver: build ID mismatch

— watchflakes

[gopherbot]

Found new dashboard test flakes for:

#!watchflakes
default <- repo == "sys" && section == "Building packages and commands for linux/loong64." && test == ""

2023-08-25 20:53 linux-loong64-3a5000 sys@51546915 go@38db2df0 (log)

go tool dist: unexpected stale targets reported by /tmp/workdir-host-linux-loong64-3a5000/go/pkg/tool/linux_loong64/go_bootstrap list -gcflags="" -ldflags="" for [cmd] (consider rerunning with GOMAXPROCS=1 GODEBUG=gocachehash=1):
	STALE cmd/pprof: stale dependency: cmd/vendor/github.com/google/pprof/internal/driver
	STALE cmd/vendor/github.com/google/pprof/driver: stale dependency: cmd/vendor/github.com/google/pprof/internal/driver
	STALE cmd/vendor/github.com/google/pprof/internal/driver: build ID mismatch

— watchflakes

[bcmills]

(attn @golang/loong64)