arrow

PARQUET-2130:  Fix crash in debug with non-standard key names.

SetListData in array_nested.cc has a DCHECK that the map type matches
the type of the child struct. When a Parquet file has a non-standard
field name for a map key(not "key"), the struct would have the alternate
name whereas the maptype would not, triggering the DCHECK. The fix is to
call the appropriate MapType constructor so the key field name is
preserved. This is very similar to ARROW-13735.

Closes #12488 from tachyonwill/arrow_map

Authored-by: William Butler <wab@google.com>
Signed-off-by: Micah Kornfield <emkornfield@gmail.com>