Input: goldfish - allow compile the driver with COMPILE_TEST

The driver depends on GOLDFISH but there isn't a build dependency
so it's a good idea to allow the driver to be built even if that
option is disabled, if the COMPILE_TEST option is enabled.

That way, the driver can be built with a config generated by make
allyesconfig and can be checked if a patch would break the build.

Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>