warning: setlocale: LC_ALL: cannot change locale on foreign distro

[Jack Hill]

Hello Guix,

I'm setting up Guix on a foreign distro (CentOS 7). I'm working on getting 
locales right per section 2.6.1 of the manual. I have installed the 
guix-locales package in buth my user's and root's profile, and have 
restarted guix-daemon. However, when I run package installation 
opterations, I see the following message,

```
/gnu/store/q19l04vd2za80mk1845pz7r8cz29qk43-bash-minimal-4.4.23/bin/bash: 
warning: setlocale: LC_ALL: cannot change locale (en_US.utf8)
```

GUIX_LOCPATH is set to /home/jackhill/.guix-profile/lib/locale

What am I missing?

```
$ guix describe
Generation 2    Jun 03 2019 10:54:12    (current)
  guix 3092f1b
    repository URL: https://git.savannah.gnu.org/git/guix.git
    branch: master
    commit: 3092f1b835d79655eecb2f8a79dda20ad9ba6bd6
```

Thanks,
Jack