remove unused TransposeINT8MKLDNNOpKernel for higher UT coverage

[lidanqing-intel]

remove unused TransposeINT8MKLDNNOpKernel for higher UT coverage.
This TransposeINT8MKLDNNOpKernel only surpport axis with [0, 2, 3, 1]

The funciton coverage has similar problem as in #15615 (comment)

coverage of transpose_mkldnn_op.cc

--	Lines	Functions
Before	72.9 %	27.8 %
After	98.2%	41.7%

[luotao1]

It seems random fails on Python35 three times:

1. http://ci.paddlepaddle.org/viewLog.html?buildId=131032&tab=buildLog&buildTypeId=Paddle_PrCiPython35&logTab=tree&filter=all&_focus=11593

[18:13:17]	The following tests FAILED:
[18:13:17]		214 - test_dist_mnist_multi_comm (Timeout)
[18:13:17]	Errors while running CTest
[18:13:24]	23/23 Test #491: test_dist_mnist_hallreduce ................***Timeout 350.02 sec

2. http://ci.paddlepaddle.org/viewLog.html?buildId=131232&tab=buildLog&buildTypeId=Paddle_PrCiPython35&logTab=tree&filter=all&_focus=11567

[03:44:59]	 8/13 Test #484: test_dist_allreduce_op ...................***Failed   12.05 sec
[03:44:59]	W0725 03:44:50.381258 25062 init.cc:162] AVX is available, Please re-compile on local machine
[03:44:59]	� X>

3. http://ci.paddlepaddle.org/viewLog.html?tab=buildLog&buildTypeId=Paddle_PrCiPython35&buildId=131286&_focus=11580

[06:50:39]	25/25 Test #553: test_dist_se_resnext_sync .................***Timeout 350.03 sec
[06:50:39]	Errors while running CTest

[luotao1]

@tianshuo78520a Could you help see it?

[jczaja]

Move into good direction! LGTM