Adjust error handling in kernfs rename.
Adjust error handling in kernfs rename.

Read-only directories (e.g. under /sys, /proc) should return EPERM for rename.

PiperOrigin-RevId: 339979022

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