Improve wording of incorrect-locale-subdir

[jengelh]

[  133s] baloo5-file-lang.noarch: E: incorrect-locale-subdir /usr/share/locale/kf5/ar

Proposed new wording:

E: incorrect-locale-subdir /usr/share/locale/kf5/ar: "kf5" is not a recognized locale.

[Conan-Kudo]

We'd probably want to rename the error if that's the actual root cause. invalid-locale-subdir, maybe?

[scarabeusiv]

I wonder if kde really install the locales there so it is expected and correct behaviour too.

[Conan-Kudo]

It doesn't in Fedora, seems to be an openSUSE specific bug.

[scarabeusiv]

Also this is in the 1.0 acting the same, so we can fix it in 2.1 ;)