[SPARK-20090][FOLLOW-UP] Revert the deprecation of names in PySpark

## What changes were proposed in this pull request?
Deprecating the field `name` in PySpark is not expected. This PR is to revert the change.

## How was this patch tested?
N/A

Author: gatorsmile <[email protected]>

Closes #20595 from gatorsmile/removeDeprecate.

(cherry picked from commit 407f672)
Signed-off-by: hyukjinkwon <[email protected]>

Author: gatorsmile

python/pyspark/sql/types.py

@@ -455,9 +455,6 @@ class StructType(DataType):
     Iterating a :class:`StructType` will iterate its :class:`StructField`\\s.
     A contained :class:`StructField` can be accessed by name or position.
 
-    .. note:: `names` attribute is deprecated in 2.3. Use `fieldNames` method instead
-        to get a list of field names.
-
     >>> struct1 = StructType([StructField("f1", StringType(), True)])
     >>> struct1["f1"]
     StructField(f1,StringType,true)