samples/kobject: be explicit in the module license

Rusty pointed out that the module license should be "GPL v2" to properly
match the notice at the top of the files, so make that change.

Reported-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --cc samples/kobject/kobject-example.c
Simple merge

diff --cc samples/kobject/kset-example.c
Simple merge