syscall: Correct length of GNU/Linux abstract Unix domain sockaddr.
syscall: Correct length of GNU/Linux abstract Unix domain sockaddr.

R=rsc, iant2
CC=golang-dev
http://codereview.appspot.com/3974044

tv42/old-go,gnanderson/go,apparentlymart/golang,gnanderson/go,tv42/old-go,pombredanne/go-deleteme,ssrl/go,gnanderson/go,dsriram/golang,pombredanne/go-deleteme,ssrl/go,gnanderson/go,dsriram/golang,ssrl/go,apparentlymart/golang,apparentlymart/golang,gnanderson/go,tv42/old-go,pombredanne/go-deleteme,dsriram/golang,tv42/old-go,pombredanne/go-deleteme,tv42/old-go,gnanderson/go,pombredanne/go-deleteme,dsriram/golang,dsriram/golang,dsriram/golang,apparentlymart/golang,ssrl/go,apparentlymart/golang,apparentlymart/golang,gnanderson/go,dsriram/golang,tv42/old-go,tv42/old-go,pombredanne/go-deleteme,apparentlymart/golang,ssrl/go,ssrl/go,pombredanne/go-deleteme,ssrl/go