[llvm] [llvm][doc] Fix return type `vector.histogram` in LangRef examples (NFC) (PR #113172)

[Benjamin Maxwell via llvm-commits]

https://github.com/MacDue created https://github.com/llvm/llvm-project/pull/113172

The `@llvm.experimental.vector.histogram.add` returns void.

>From ef29db7a9abd60b33a115e5870a16fbb2f916944 Mon Sep 17 00:00:00 2001
From: Benjamin Maxwell <benjamin.maxwell at arm.com>
Date: Mon, 21 Oct 2024 14:53:19 +0000
Subject: [PATCH] [llvm][doc] Fix return type `vector.histogram` in LangRef
 examples (NFC)

The `@llvm.experimental.vector.histogram.add` returns void.
---
 llvm/docs/LangRef.rst | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/llvm/docs/LangRef.rst b/llvm/docs/LangRef.rst
index 566d0d4e4e81a3..b83675c6ed97aa 100644
--- a/llvm/docs/LangRef.rst
+++ b/llvm/docs/LangRef.rst
@@ -19925,8 +19925,8 @@ More update operation types may be added in the future.
 
 ::
 
-    declare <8 x i32> @llvm.experimental.vector.histogram.add.v8p0.i32(<8 x ptr> %ptrs, i32 %inc, <8 x i1> %mask)
-    declare <vscale x 2 x i64> @llvm.experimental.vector.histogram.add.nxv2p0.i64(<vscale x 2 x ptr> %ptrs, i64 %inc, <vscale x 2 x i1> %mask)
+    declare void @llvm.experimental.vector.histogram.add.v8p0.i32(<8 x ptr> %ptrs, i32 %inc, <8 x i1> %mask)
+    declare void @llvm.experimental.vector.histogram.add.nxv2p0.i64(<vscale x 2 x ptr> %ptrs, i64 %inc, <vscale x 2 x i1> %mask)
 
 Arguments:
 """"""""""