Add a few livepatch modules and simple target modules that the included
regression suite can run tests against:

  - basic livepatching (multiple patches, atomic replace)
  - pre/post (un)patch callbacks
  - shadow variable API
Signed-off-by: NJoe Lawrence <joe.lawrence@redhat.com>
Signed-off-by: NPetr Mladek <pmladek@suse.com>
Tested-by: NMiroslav Benes <mbenes@suse.cz>
Tested-by: NAlice Ferrazzi <alice.ferrazzi@gmail.com>
Acked-by: NJoe Lawrence <joe.lawrence@redhat.com>
Acked-by: NJosh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>