linuxkpi: move kobject_create to .c file

[imp]

Summary

kobject_create knows the size of struct kobject. Move it to
linux_compat.c so this knowledge is confined to the loadable module and
not the clients.

Sponsored by: Netflix

[emaste]

I assume there is no performance concern with this.

(a minute later)
It looks like Linux defines this in a .c file, so sounds good.

[imp]

In D34767#788051, @emaste wrote:

I assume there is no performance concern with this.

(a minute later)
It looks like Linux defines this in a .c file, so sounds good.

None of this series of commits are performance critical. They are all startup-only or otherwise rare events as far as I can tell...