nir: Misc. cleanups
I started working on improving nir_lower_input_attachments() and these are a few cleanups I did along the way. I think they're probably worth it on their own so here they are in a stand-alone MR.
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I started working on improving nir_lower_input_attachments() and these are a few cleanups I did along the way. I think they're probably worth it on their own so here they are in a stand-alone MR.