LinuxKPI: Stub sysfs_remove_link in linux/sysfs.h

sysfs_create_link is stubbed already. Stub sysfs_remove_link too to be
feature-complete.

Sponsored by: Serenity Cyber Security, LLC
Reviewed by: emaste
MFC after: 1 week

(cherry picked from commit 4e7aa03b7076353af4b960ade67f093af5736d38)