[llvm] [BOLT] Fix unused variable warning (PR #93253)

[Sayhaan Siddiqui via llvm-commits]

https://github.com/sayhaan created https://github.com/llvm/llvm-project/pull/93253

This fixes

```
/data/sandcastle/boxes/trunk-grepo-llvm-c2-grepo/llvm-project/bolt/lib/Rewrite/DWARFRewriter.cpp:76:45: warning: variable 'AbbrDecl' set but not used [-Wunused-but-set-variable]

   76 |     if (const DWARFAbbreviationDeclaration *AbbrDecl =
```

>From 0082a6bd87da5ac13058311141163dee4307ca2b Mon Sep 17 00:00:00 2001
From: Sayhaan Siddiqui <sayhaan at meta.com>
Date: Thu, 23 May 2024 16:12:51 -0700
Subject: [PATCH] [BOLT] Fix unused variable warning

---
 bolt/lib/Rewrite/DWARFRewriter.cpp | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/bolt/lib/Rewrite/DWARFRewriter.cpp b/bolt/lib/Rewrite/DWARFRewriter.cpp
index d582ce7b33a27..d2a7cbdbb1a2b 100644
--- a/bolt/lib/Rewrite/DWARFRewriter.cpp
+++ b/bolt/lib/Rewrite/DWARFRewriter.cpp
@@ -73,8 +73,8 @@ static void printDie(DWARFUnit &DU, uint64_t DIEOffset) {
   DWARFDataExtractor DebugInfoData = DU.getDebugInfoExtractor();
   DWARFDebugInfoEntry DIEEntry;
   if (DIEEntry.extractFast(DU, &DIEOffset, DebugInfoData, NextCUOffset, 0)) {
-    if (const DWARFAbbreviationDeclaration *AbbrDecl =
-            DIEEntry.getAbbreviationDeclarationPtr()) {
+    const DWARFAbbreviationDeclaration *AbbrDecl;
+    if (AbbrDecl = DIEEntry.getAbbreviationDeclarationPtr()) {
       DWARFDie DDie(&DU, &DIEEntry);
       printDie(DDie);
     } else {