iris, i965: Implement EXT_demote_to_helper_invocation
The NIR and backend changes already landed for the VK version, this MR updates the parser to handle the new constructs and enable it for Iris / i965. A lot of plumbing.
Edited by Caio Oliveira
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The NIR and backend changes already landed for the VK version, this MR updates the parser to handle the new constructs and enable it for Iris / i965. A lot of plumbing.