check isRootNS by ns inode
check isRootNS by ns inode

Signed-off-by: Shijiang Wei <d51735f6fb3b158a0436903895ceec01381bfb9f@gmail.com>
Change-Id: I032f834edae5c716fb2d3538285eec07aa11a902
PiperOrigin-RevId: 231318438

google/gvisor,google/gvisor,google/gvisor,google/gvisor,google/gvisor,google/gvisor,google/gvisor,google/gvisor