st/va: avoid dereference after free in vlVaDestroyImage
st/va: avoid dereference after free in vlVaDestroyImage

Cc: "11.1 11.2" <59f39c0db42d4479a46b02d4d2bc11120e37bb44@lists.freedesktop.org>
Reviewed-by: Emil Velikov <4c996f2f093ddd0585a556460b4cc3ba555546ef@gmail.com>
Tested-by: Julien Isorce <2904e845d63d102574cbb95a4bcdefac0a5d7af0@samsung.com>

metora/MesaGLSLCompiler,metora/MesaGLSLCompiler,metora/MesaGLSLCompiler