Improve memory allocation on native row to column operator

[zhouyuan]

Is your feature request related to a problem or challenge? Please describe what you are trying to do.
Currently R2C will allocate a 128MB(hard-coded) chunk for the following operation.
https://github.com/oap-project/gazelle_plugin/blob/master/native-sql-engine/core/src/main/scala/com/intel/oap/execution/ArrowRowToColumnarExec.scala#L103

Describe the solution you'd like
This should be improved by estimate/calculate the real memory usage

• for fixed width type, it's easy to calculate the detailed memory size
• for string, we should estimate the size and do re-alloc in case the memory is not enough

Describe alternatives you've considered
N/A

Additional context
N/A