[clang] [clang][AMDGPU] Update amdgpu_waves_per_eu attr docs (PR #74587)

[Pierre van Houtryve via cfe-commits]

https://github.com/Pierre-vh created https://github.com/llvm/llvm-project/pull/74587

None

>From f4f909df09dda7e2d21389f7b44f67e89997c44b Mon Sep 17 00:00:00 2001
From: pvanhout <pierre.vanhoutryve at amd.com>
Date: Wed, 6 Dec 2023 12:47:56 +0100
Subject: [PATCH] [clang][AMDGPU] Update amdgpu_waves_per_eu attr docs

---
 clang/include/clang/Basic/AttrDocs.td | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/clang/include/clang/Basic/AttrDocs.td b/clang/include/clang/Basic/AttrDocs.td
index bbe4de94cbabe..88f7c65e6e847 100644
--- a/clang/include/clang/Basic/AttrDocs.td
+++ b/clang/include/clang/Basic/AttrDocs.td
@@ -2659,8 +2659,9 @@ An error will be given if:
   - Specified values violate subtarget specifications;
   - Specified values are not compatible with values provided through other
     attributes;
-  - The AMDGPU target backend is unable to create machine code that can meet the
-    request.
+
+The AMDGPU target backend will emit a warning whenever it is unable to
+create machine code that meets the request.
   }];
 }