* Revert "Align CTC grad scale same with ESPNet (#34729)"

This reverts commit 10f9644c.

* ctc grad compute on gpu

delete main function

1. optimize the error message of softmax_with_cross_entropy_op;2. add input value check for cross_entropy, if the dimention of input is zero, raise error. test = develop

* dygraph support more ctc grad scale

* scale for 1.x

* fix unitest

* fix unitest

* format code

* fix unittest

* fix log info

* unittest cov

* fix format;notest,test=cpu,coverage

* skip ctc_loss egs;test=cpu

* warpctc grad cov;test=coverage

* add dygraph test;test=coverage

* format;test=cpu,coverage

* format;test=cpu

* add api compat;test=cpu

* add cpu test

* rename

* rename

* fix

* fix test

* format

* eigen cpu

* eigen gpu grad pass

* cuda gpu pass

* format

* fix ci

* support margin loss (arcface, cosface, sphereface)

* fix paddle.optimizer test=document_fix

* fix paddle.optimizer test=document_fix

* fix bugs in paddle.nn.functional document test=document_fix

* fix bugs in paddle.nn.functional document test=document_fix

* fix bugs in paddle.nn.functional document test=document_fix

* fix bugs in paddle.nn.functional document test=document_fix

* cache core.ops, test=develop

* refine, test=develop

* Add deprecated warning info.

* Add unittest for deprecated decorator.

* Add warning info for tensor.grad

add __all__=[] to python files not in API public list; import * only support in API public list files (#32643)

* update 2.0 public api in nn

* replace Chinese character cause error in ci;synchronization with pr:#32588 to avoid 'ascii' codec in python2

* numbers used in paddle.nn.functional.norm but not imported

* fix cross_entropy calculation error

* add unittest and fix static

* add norm_by_times param to ctc_loss

* fix doc,test=develop