[PATCH vkd3d 4/5] tests: Add some basic tests for #if and related preprocessor directives.

[Matteo Bruni]

Signed-off-by: Matteo Bruni <mbruni at codeweavers.com>
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No need to go and add my signoff if the patches are already committed
and it would require more than trivial effort. This is mostly a try
run for me...