net/http/pprof: fix doc for /debug/pprof/

Fixes #4548.

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/6944053

src/pkg/net/http/pprof/pprof.go

@@ -34,9 +34,8 @@
 //
 //	go tool pprof http://localhost:6060/debug/pprof/block
 //
-// Or to view all available profiles:
-//
-//	go tool pprof http://localhost:6060/debug/pprof/
+// To view all available profiles, open http://localhost:6060/debug/pprof/
+// in your browser.
 //
 // For a study of the facility in action, visit
 //