[cudax->libcu++] Move buffer type from cudax to libcu++

[pciolkosz]

PR moving last bits of the buffer type and de-duplicating the __memory_accessibility enum

[github-actions[bot]]

😬 CI Workflow Results

🟥 Finished in 1h 42m: Pass: 30%/120 | Total: 1d 00h | Max: 1h 38m | Hits: 78%/20847

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[github-actions[bot]]

😬 CI Workflow Results

🟥 Finished in 58m 39s: Pass: 61%/120 | Total: 16h 00m | Max: 48m 35s | Hits: 98%/39998

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