i965/fs: do d2x lowering before simd splitting
i965/fs: do d2x lowering before simd splitting

So that we can have gen7 split large writes produced by this lowering pass.

Signed-off-by: Samuel Iglesias Gonsálvez <b753b212f30aed827c3eea2e437609dc37310153@igalia.com>
Reviewed-by: Francisco Jerez <5906ff32bdd9fd8db196f6ba5ad3afd6f9257ea5@riseup.net>

metora/MesaGLSLCompiler,metora/MesaGLSLCompiler,metora/MesaGLSLCompiler