runtime: fix heap coalescing bug introduced in cl/9802043 mheap.map become a pointer, so nelem(h->map) returns 1 rather than the map size. As the result coalescing with subsequent spans does not happen.
runtime: fix heap coalescing bug introduced in cl/9802043
mheap.map become a pointer, so nelem(h->map) returns 1 rather than the map size.
As the result coalescing with subsequent spans does not happen.

R=golang-dev, khr
CC=golang-dev
https://codereview.appspot.com/9649046

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