all: remove redundant type conversion

[cuishuang]

[gopherbot]

This PR (HEAD: b8ecf761efe6a2eec78a805a99d778bdcdb938f9) has been imported to Gerrit for code review.

Please visit https://go-review.googlesource.com/c/crypto/+/429016 to see it.

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[gopherbot]

Message from Ian Lance Taylor:

Patch Set 1: Run-TryBot+1 Code-Review+2

(1 comment)

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Please don’t reply on this GitHub thread. Visit golang.org/cl/429016. After addressing review feedback, remember to publish your drafts!

[gopherbot]

Message from Gopher Robot:

Patch Set 1:

(1 comment)

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Please don’t reply on this GitHub thread. Visit golang.org/cl/429016. After addressing review feedback, remember to publish your drafts!

[gopherbot]

Message from Gopher Robot:

Patch Set 1: TryBot-Result+1

(1 comment)

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Please don’t reply on this GitHub thread. Visit golang.org/cl/429016. After addressing review feedback, remember to publish your drafts!

[gopherbot]

Message from Michael Knyszek:

Patch Set 1: Code-Review+1

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Please don’t reply on this GitHub thread. Visit golang.org/cl/429016. After addressing review feedback, remember to publish your drafts!

[gopherbot]

Message from shuang cui:

Patch Set 1:

(1 comment)

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[gopherbot]

This PR is being closed because golang.org/cl/429016 has been merged.