st/nine: Do not leak private data in volume9.
st/nine: Do not leak private data in volume9.

This->data was allocated by nine, but not freed.

Reviewed-by: Axel Davy <2b6ef604b998fb81662f85c329e4fc020eae8e5d@ens.fr>
Signed-off-by: Patrick Rudolph <2af63f351b8bda7baf3a287b873bcd3ca66a59bb@das-labor.org>

metora/MesaGLSLCompiler,metora/MesaGLSLCompiler,metora/MesaGLSLCompiler