Because layer changes may take some time allow the user to cancel out of
the dialogue and prevent Hob from applying any of the changes made.
(Bitbake rev: a2d1c035a5dd3d112a887e4386dfaf9b0c37c104)
Signed-off-by: Joshua Lock <josh@linux.intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>