arrow

ARROW-11341: [Python] [Gandiva] Add NULL/None checks to Gandiva builder functions (#9289)

If these functions were passed None as an argument, they caused segfaults. As an example:

```python
import pyarrow
import pyarrow.gandiva as gandiva

builder = gandiva.TreeExprBuilder()
field = pyarrow.field('whatever', type=pyarrow.date64())
date_col = builder.make_field(field)

func = builder.make_function('less_than_or_equal_to', [date_col, None], pyarrow.bool_())

condition = builder.make_condition(func)

# Will segfault on this line:
gandiva.make_filter(pyarrow.schema([field]), condition)
```

Lead-authored-by: Will Jones <willjones127@gmail.com>
Co-authored-by: Will Jones <will.jones@mscience.com>
Signed-off-by: David Li <li.davidm96@gmail.com>