Merge branch 'jk/ls-files-recurse-submodules-fix'

"ls-files --recurse-submodules" did not quite work well in a
project with nested submodules.

* jk/ls-files-recurse-submodules-fix:
ls-files: fix path used when recursing into submodules
ls-files: fix recurse-submodules with nested submodules