fix: Disable api-demo due to meson

Signed-off-by: Rahix <rahix@rahix.de>

hw-tests/meson.build

-subdir('api-demo/')
+# Disabled due to meson bug in older version
+# subdir('api-demo/')
 subdir('bmatest/')
 subdir('bmetest/')
 subdir('dual-core/')