[oneDNN] Remove MKL blocked format test code
@ezhulenev  I noticed that "AMD ROCSm" and "Windows Bazel check do not pass.

However, PR change should not cause the problem, as NativeFormatEnabled currently always returns "true" value. 
Later on, I will create another PR to get rid of "NativeFormatEnabled" methods and clean up related caller code. 
 @cantonios @ezhulenev  Thanks a lot for the approval!
Remove MKL blocked format test code.

MKL blocked format is not supported any more.