misc/cgo/life: explicitly specify library for assert function (fixes windows/amd64 build)

R=golang-dev, dave
CC=golang-dev, minux.ma
https://golang.org/cl/6461065

misc/cgo/life/life.go

@@ -6,6 +6,7 @@
 
 package life
 
+// #cgo windows LDFLAGS: -lmsvcrt
 // #include "life.h"
 import "C"