riscv64: add disassembly support and tests for zacas

[newborn22]

Add disassembly support and tests for Zacas extension on RISCV64.

[gopherbot]

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[gopherbot]

Message from Gopher Robot:

Patch Set 1:

(1 comment)

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[gopherbot]

Message from Weihong Qiu:

Patch Set 1:

(1 comment)

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[gopherbot]

Message from Joel Sing:

Patch Set 1: Commit-Queue+1

(1 comment)

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[gopherbot]

Message from Go LUCI:

Patch Set 1:

Dry run: CV is trying the patch.

Bot data: {"action":"start","triggered_at":"2026-03-27T14:07:59Z","revision":"c1537c9c525283e27e5bdaa3f27ea5ee08d07b27"}

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Message from Joel Sing:

Patch Set 1: -Commit-Queue

(Performed by <GERRIT_ACCOUNT_60063> on behalf of <GERRIT_ACCOUNT_13640>)

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Message from Go LUCI:

Patch Set 1:

This CL has passed the run

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Message from Go LUCI:

Patch Set 1: LUCI-TryBot-Result+1

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[gopherbot]

Message from Joel Sing:

Patch Set 1: Commit-Queue+1

(1 comment)

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[gopherbot]

Message from Go LUCI:

Patch Set 1:

Dry run: CV is trying the patch.

Bot data: {"action":"start","triggered_at":"2026-03-27T14:22:23Z","revision":"c1537c9c525283e27e5bdaa3f27ea5ee08d07b27"}

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Message from Joel Sing:

Patch Set 1: -Commit-Queue

(Performed by <GERRIT_ACCOUNT_60063> on behalf of <GERRIT_ACCOUNT_13640>)

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Message from Go LUCI:

Patch Set 1:

This CL has passed the run

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Message from Mark Ryan:

Patch Set 1:

(1 comment)

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Message from Mark Ryan:

Patch Set 1:

(1 comment)

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