[bug-diffutils] - Directories compare doesn't show all differences

Description of problem:
Directories compare with --brief doesn't show all differencies

Version-Release number of selected component (if applicable):
3.6

How reproducible:
always

Steps to Reproduce:
1. create 2 directories dir1 and dir2
2. in dir1 create README file
3. in dir2 create README directory
4. in dir2/README directory create some files - readme1.txt readme2.txt
5. do diff -r --brief dir1/ dir2/

Actual results:
file dir1/README is a regular file while file dir2/README is a directory

Information about files in dir2/README in compare to dir1 is not
present - also difference

Expected results:
Show all difference as expected