loongarch: Use intrinsics::simd for vbit{clr,rev,set}

[heiher]

No description provided.

[rustbot]

r? @folkertdev

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The reviewer was selected based on:

• Owners of files modified in this PR: @Amanieu, @folkertdev, @sayantn
• @Amanieu, @folkertdev, @sayantn expanded to Amanieu, folkertdev, sayantn
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[heiher]

Ref:

• lsx_vbitclr_b
• lsx_vbitclr_h
• lsx_vbitclr_w
• lsx_vbitclr_d
• lsx_vbitset_b
• lsx_vbitset_h
• lsx_vbitset_w
• lsx_vbitset_d
• lsx_vbitrev_b
• lsx_vbitrev_h
• lsx_vbitrev_w
• lsx_vbitrev_d
• lasx_xvbitclr_b
• lasx_xvbitclr_h
• lasx_xvbitclr_w
• lasx_xvbitclr_d
• lasx_xvbitset_b
• lasx_xvbitset_h
• lasx_xvbitset_w
• lasx_xvbitset_d
• lasx_xvbitrev_b
• lasx_xvbitrev_h
• lasx_xvbitrev_w
• lasx_xvbitrev_d

[folkertdev]

This PR has merge conflicts

@rustbot author

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[rustbot]

This PR was rebased onto a different main commit. Here's a range-diff highlighting what actually changed.

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[heiher]

This PR has merge conflicts

ready, thanks!