Revert "Rename src/customization/xsl/pt_br.xml to pt-BR.xml"

Authored by ltoscano on Nov 12 2018, 8:55 PM.

Description

Revert "Rename src/customization/xsl/pt_br.xml to pt-BR.xml"

This is not the right fix: this file should have the same
name as the original file from docbook-xsl.

If the fix had been easier, it would have been fixed already.

CCBUG: 400973
CCMAIL: yurchor@ukr.net

This reverts commit 54cc616215e5087ff77fb3905f98e010145c8fa9.