Last patches contain a couple of problems, unbound variables are fixed
in the attached patch.  Commit message has been reworded. 

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gnu: grub: Add locale output.

* gnu/packages/bootloaders.scm (grub): Add new phase 'install-locale-folder
to generate new output used for bootloader localization.
---
 gnu/packages/bootloaders.scm | 33 +++++++++++++++++++++++++++++----
 1 file changed, 29 insertions(+), 4 deletions(-)