[NFC] Remove unused set construction from DILocation::getMergedLocation

[jmmartinez]

Removed useless Result local variable too

[dblaikie]

Thanks - looks like I missed cleaning this up... 4 years ago when I made this change: 2a813ef208283980598202ac6453f3a777c608f5

Looks good to me

llvm/lib/IR/DebugInfoMetadata.cpp

 const DILocation *DILocation::getMergedLocation(const DILocation *LocA,
                                                 const DILocation *LocB) {
   if (!LocA || !LocB)
     return nullptr;
 
   if (LocA == LocB)
     return LocA;
 
-  SmallPtrSet<DILocation *, 5> InlinedLocationsA;
-  for (DILocation *L = LocA->getInlinedAt(); L; L = L->getInlinedAt())
-    InlinedLocationsA.insert(L);
   SmallSet<std::pair<DIScope *, DILocation *>, 5> Locations;
   DIScope *S = LocA->getScope();
   DILocation *L = LocA->getInlinedAt();
   while (S) {
     Locations.insert(std::make_pair(S, L));
     S = S->getScope();
     if (!S && L) {
       S = L->getScope();
       L = L->getInlinedAt();
     }
   }
-  const DILocation *Result = LocB;
   S = LocB->getScope();
   L = LocB->getInlinedAt();
   while (S) {
     if (Locations.count(std::make_pair(S, L)))
       break;
     S = S->getScope();
     if (!S && L) {
       S = L->getScope();
       L = L->getInlinedAt();
     }
   }
 
   // If the two locations are irreconsilable, just pick one. This is misleading,
   // but on the other hand, it's a "line 0" location.
   if (!S || !isa<DILocalScope>(S))
     S = LocA->getScope();
-  return DILocation::get(Result->getContext(), 0, 0, S, L);
+  return DILocation::get(LocA->getContext(), 0, 0, S, L);
 }
 
 Optional<unsigned> DILocation::encodeDiscriminator(unsigned BD, unsigned DF,
                                                    unsigned CI) {
   std::array<unsigned, 3> Components = {BD, DF, CI};
   uint64_t RemainingWork = 0U;
   // We use RemainingWork to figure out if we have no remaining components to
   // encode. For example: if BD != 0 but DF == 0 && CI == 0, we don't need to