misc/pprof: register cnew and runtime.cnewarray as malloc wrappers.
misc/pprof: register cnew and runtime.cnewarray as malloc wrappers.

These functions were introduced by revision 139919984600
and should not show up on profiles for consistency.

R=golang-dev, iant
CC=golang-dev
https://codereview.appspot.com/10003043

wesolows/golang,wesolows/golang-old,firebitsbr/golang-old,wesolows/golang,wesolows/golang,firebitsbr/golang-old,firebitsbr/golang-old,wesolows/golang-old,firebitsbr/golang-old,wesolows/golang,firebitsbr/golang-old,wesolows/golang-old,wesolows/golang-old,wesolows/golang,wesolows/golang-old,firebitsbr/golang-old,firebitsbr/golang-old,wesolows/golang,wesolows/golang-old,firebitsbr/golang-old,wesolows/golang-old,wesolows/golang