runtime: fix arm build.
runtime: fix arm build.

More functions needs to be marked as no stack split.

R=golang-dev, rsc
CC=golang-dev
https://codereview.appspot.com/11963044

tv42/old-go,apparentlymart/golang,apparentlymart/golang,tv42/old-go,apparentlymart/golang,apparentlymart/golang,apparentlymart/golang,pombredanne/go-deleteme,tv42/old-go,pombredanne/go-deleteme,pombredanne/go-deleteme,pombredanne/go-deleteme,tv42/old-go,apparentlymart/golang,pombredanne/go-deleteme,pombredanne/go-deleteme,pombredanne/go-deleteme,tv42/old-go,apparentlymart/golang,tv42/old-go,tv42/old-go