cmd/vet/all: remove pprof from the whitelist

Updates #19322

Change-Id: I610f40d874f499e52db3356a3da54538dac55242
Reviewed-on: https://go-review.googlesource.com/37618
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>

src/cmd/vet/all/main.go

@@ -191,9 +191,6 @@ var ignorePathPrefixes = [...]string{
 	// TODO: If vet ever uses go/loader and starts working off source,
 	// this problem will likely go away.
 	"fmt/fmt_test.go",
-	// Ignore pprof for the moment to get the builders happy.
-	// TODO: Fix all the issues and reinstate.
-	"cmd/vendor/github.com/google/pprof",
 }
 
 func vetPlatforms(pp []platform) {