do not close pipe in write side
do not close pipe in write side

hyper_container_stage0 shares fd table with init, right now stage0
may close pipe before init read the pipe. this will cause container
fail to start.

Signed-off-by: Gao feng <7f710758e13fe1707f3aa2e93d3a8f5444b6a90e@gmail.com>

gnawux/hyperstart,MarioCarrilloA/hyperstart,gao-feng/hyperstart,laijs/hyperstart,MarioCarrilloA/hyperstart,hyperhq/hyperstart,bergwolf/hyperstart,laijs/hyperstart,gnawux/hyperstart,gao-feng/hyperstart,gnawux/hyperstart,hyperhq/hyperstart,MarioCarrilloA/hyperstart,bergwolf/hyperstart