anv: build the core vulkan only once
anv: build the core vulkan only once

Introduce a static library libvulkan_common.la that is used by
libvukan_intel.la and libvulkan_test.la.

Signed-off-by: Emil Velikov <f20878473f414da183da19ee25c8722cc1d711e4@collabora.com>
Acked-by: Jason Ekstrand <68c46a606457643eab92053c1c05574abb26f861@jlekstrand.net>

metora/MesaGLSLCompiler,metora/MesaGLSLCompiler,metora/MesaGLSLCompiler