doc: remove pprof TODOs from go1.8.html

There is nothing notable to mention as far as users are concerned.

Fixes #17929 (another bug tracks the remaining TODO item)

Change-Id: Id39f787581ed9d2ecd493126bb7ca27836816d4b
Reviewed-on: https://go-review.googlesource.com/34145
Reviewed-by: Michael Matloob <matloob@golang.org>

doc/go1.8.html

@@ -250,14 +250,6 @@ <h3 id="tool_pprof">Pprof</h3>
   The callgrind output now has instruction-level granularity.
 </p>
 
-<p>
-  TODO: more. proto? standalone profiles with symbols?
-<pre>
-runtime/pprof: output CPU profiles in pprof protobuf format (CL 33071)
-runtime/pprof: write profiles in protobuf format. (CL 32257)
-</pre>
-</p>
-
 <h3 id="tool_trace">Trace</h3>
 
 <p>TODO:</p>