vl: remove DRI2DriverPrimeShift compile guards
vl: remove DRI2DriverPrimeShift compile guards

DRI2DriverPrimeShift was added in dri2proto-2.8, which we now require as
of the previous commit.

Signed-off-by: Emil Velikov <f20878473f414da183da19ee25c8722cc1d711e4@collabora.com>
Reviewed-by: Matt Turner <789b315743a28dd066a4ba1459c35951c291d8a6@gmail.com>

metora/MesaGLSLCompiler,metora/MesaGLSLCompiler,metora/MesaGLSLCompiler