tar '-u' mode behaves like '-r'

[MikZyth]

Hello.

Command `tar -vuf test.tar -T filelist.txt` unconditionally adds files
from filelist.txt. So, with -T (--files-from=) option, -u mode works
like -r.

$ tar --version
tar (GNU tar) 1.35

It worked correctly in tar 1.34.

-- 
Best regards,
MikZyth.