The driver only has runtime but no build time dependency with SH_MIGOR, so
it can be built for testing purposes if the COMPILE_TEST option is enabled.

This is useful to have more build coverage and make sure that drivers are
not affected by changes that could cause build regressions.
Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>