script: fix build script regression to work on OSX

Use sed instead of cut to accomodate GNU and BSD differences

Fixes: #5240

build

@@ -11,7 +11,7 @@ GIT_SHA=`git rev-parse --short HEAD || echo "GitNotFound"`
 
 LINK_OPERATOR="="
 
-host_arch=$(GOARCH="" go env | egrep 'GOARCH=' | cut --delimiter='"' --field=2)
+host_arch=$(GOARCH="" go env | egrep 'GOARCH=' | sed 's/^GOARCH="\(.*\)".*/\1/')
 
 if [ -z "${GOARCH}" ] || [ "${GOARCH}" = "${host_arch}" ]; then
 	out="bin"