**Describe the situation**
multiIf works 10 times slower than If with single condition.

**How to reproduce**
ClickHouse version 21.10

```

SELECT count()
FROM numbers_mt(1000000000)
WHERE NOT ignore(multiIf(number = 0, NULL, toNullable(number)))

┌────count()─┐
│ 1000000000 │
└────────────┘

1 rows in set. Elapsed: 10.267 sec. Processed 1.00 billion rows, 8.00 GB (97.41 million rows/s., 779.25 MB/s.)

SELECT count()
FROM numbers_mt(1000000000)
WHERE NOT ignore(If(number = 0, NULL, toNullable(number)))

┌────count()─┐
│ 1000000000 │
└────────────┘

1 rows in set. Elapsed: 1.010 sec. Processed 1.00 billion rows, 8.00 GB (990.63 million rows/s., 7.93 GB/s.)
```

**Expected performance**
The same performance for multiIf and if.

#include <Core/Settings.h>
#include <Interpreters/TreeOptimizer.h>
#include <Interpreters/TreeRewriter.h>
#include <Interpreters/OptimizeIfChains.h>
#include <Interpreters/OptimizeIfWithConstantConditionVisitor.h>
#include <Interpreters/WhereConstraintsOptimizer.h>
#include <Interpreters/SubstituteColumnOptimizer.h>
#include <Interpreters/TreeCNFConverter.h>
#include <Interpreters/ArithmeticOperationsInAgrFuncOptimize.h>
#include <Interpreters/DuplicateOrderByVisitor.h>
#include <Interpreters/GroupByFunctionKeysVisitor.h>
#include <Interpreters/AggregateFunctionOfGroupByKeysVisitor.h>
#include <Interpreters/RewriteAnyFunctionVisitor.h>
#include <Interpreters/RemoveInjectiveFunctionsVisitor.h>
#include <Interpreters/RedundantFunctionsInOrderByVisitor.h>
#include <Interpreters/RewriteCountVariantsVisitor.h>
#include <Interpreters/MonotonicityCheckVisitor.h>
#include <Interpreters/ConvertStringsToEnumVisitor.h>
#include <Interpreters/ConvertFunctionOrLikeVisitor.h>
#include <Interpreters/RewriteFunctionToSubcolumnVisitor.h>
#include <Interpreters/Context.h>
#include <Interpreters/ExternalDictionariesLoader.h>
#include <Interpreters/GatherFunctionQuantileVisitor.h>
#include <Interpreters/UserDefinedExecutableFunctionFactory.h>
#include <Parsers/ASTExpressionList.h>
#include <Parsers/ASTFunction.h>
#include <Parsers/ASTLiteral.h>