[OpenMP][mlir] Fix return for isHostDeviceOp for omp.target_allocmem and omp.target_freemem (llvm#4239)

Author: ronlieb

mlir/lib/Target/LLVMIR/Dialect/OpenMP/OpenMPToLLVMIRTranslation.cpp

@@ -6436,7 +6436,7 @@ static bool isHostDeviceOp(Operation *op) {
 
   if (mlir::isa<omp::TargetAllocMemOp>(op) ||
       mlir::isa<omp::TargetFreeMemOp>(op))
-    return true;
+    return false;
 
   if (auto parentFn = op->getParentOfType<LLVM::LLVMFuncOp>()) {
     if (auto declareTargetIface =