crypto/elliptic: change a variable name that have the same name as keywords

[mohanson]

Change the variable name from byte to b, and use range over int to
simplify the loop.

[gopherbot]

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[gopherbot]

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Patch Set 1:

(1 comment)

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[gopherbot]

Message from 叶万标:

Patch Set 1:

(2 comments)

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[gopherbot]

Message from qiu laidongfeng2:

Patch Set 2: Code-Review+1 Commit-Queue+1

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Message from Go LUCI:

Patch Set 2:

Dry run: CV is trying the patch.

Bot data: {"action":"start","triggered_at":"2025-07-25T14:19:12Z","revision":"41f7fb666f826bd2b5a1bb278130ebceed490300"}

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[gopherbot]

Message from qiu laidongfeng2:

Patch Set 2: -Commit-Queue

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Patch Set 2:

This CL has passed the run

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Patch Set 2: LUCI-TryBot-Result+1

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Message from Roland Shoemaker:

Patch Set 2: Code-Review+2

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Message from Michael Knyszek:

Patch Set 2: Code-Review+1

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