[DebugInfo] Avoid repeated hash lookups (NFC) (llvm#128395)

Author: kazutakahirata

llvm/lib/DebugInfo/LogicalView/Readers/LVCodeViewReader.cpp

@@ -162,11 +162,12 @@ void LVCodeViewReader::cacheRelocations() {
   for (const SectionRef &Section : getObj().sections()) {
     const coff_section *CoffSection = getObj().getCOFFSection(Section);
 
+    auto &RM = RelocMap[CoffSection];
     for (const RelocationRef &Relocacion : Section.relocations())
-      RelocMap[CoffSection].push_back(Relocacion);
+      RM.push_back(Relocacion);
 
     // Sort relocations by address.
-    llvm::sort(RelocMap[CoffSection], [](RelocationRef L, RelocationRef R) {
+    llvm::sort(RM, [](RelocationRef L, RelocationRef R) {
       return L.getOffset() < R.getOffset();
     });
   }