Module: check to see if we have a built in module with the same name

Module: check to see if we have a built in module with the same name

When trying to load a module with the same name as a built-in one, a
scary kobject backtrace comes up.  Prevent that from checking for this
condition and warning the user as to what exactly is going on.

Cc: Rusty Russell <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Andrew Morton <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
Signed-off-by: Rusty Russell <[email protected]>