[LoopUnswitch] Remove redundant condition. (NFC) (llvm#107893)

Remove redundant condition from  '!A || (A && B)' to '!A || B' 

Fixes: llvm#99799

Author: AmrDeveloper

llvm/lib/Transforms/Scalar/SimpleLoopUnswitch.cpp

@@ -770,8 +770,7 @@ static bool unswitchTrivialSwitch(Loop &L, SwitchInst &SI, DominatorTree &DT,
     // instruction in the block.
     auto *TI = BBToCheck.getTerminator();
     bool isUnreachable = isa<UnreachableInst>(TI);
-    return !isUnreachable ||
-           (isUnreachable && (BBToCheck.getFirstNonPHIOrDbg() != TI));
+    return !isUnreachable || BBToCheck.getFirstNonPHIOrDbg() != TI;
   };
 
   SmallVector<int, 4> ExitCaseIndices;