i18n: install Python translations from a sensible place

- put the installation code in lang/ rather than among the modules
- remove useless indirection through CMake macro

CMakeModules/CalamaresAddTranslations.cmake

@@ -48,22 +48,6 @@ macro(add_calamares_translations language)
     )
 endmacro()
 
-# Internal macro for Python translations
-#
-# Translations of the Python modules that don't have their own
-# lang/ subdirectories -- these are collected in top-level
-# lang/python/<lang>/LC_MESSAGES/python.mo
-macro(add_calamares_python_translations language)
-    set( CALAMARES_LANGUAGES "" )
-    list( APPEND CALAMARES_LANGUAGES ${ARGV} )
-
-    install_calamares_gettext_translations( python
-        SOURCE_DIR ${CMAKE_SOURCE_DIR}/lang/python
-        FILENAME python.mo
-        RENAME calamares-python.mo
-    )
-endmacro()
-
 # Installs a directory containing language-code-labeled subdirectories with
 # gettext data into the appropriate system directory. Allows renaming the
 # .mo files during install to avoid namespace clashes.

lang/CMakeLists.txt

@@ -5,8 +5,16 @@
 #
 ###
 
+include( CalamaresAddTranslations )
+
 find_package(Qt5 COMPONENTS Xml)
 if( Qt5Xml_FOUND )
     add_executable(txload txload.cpp)
     target_link_libraries(txload Qt5::Xml)
 endif()
+
+install_calamares_gettext_translations( python
+    SOURCE_DIR ${CMAKE_SOURCE_DIR}/lang/python
+    FILENAME python.mo
+    RENAME calamares-python.mo
+)

src/modules/CMakeLists.txt

@@ -73,8 +73,6 @@ foreach( _category ${_use_categories} )
     endif()
 endforeach()
 
-add_calamares_python_translations( ${CALAMARES_TRANSLATION_LANGUAGES} )
-
 # TODO:3.3: Use FindPython3
 if ( BUILD_TESTING AND BUILD_SCHEMA_TESTING AND PYTHONINTERP_FOUND AND PYTHON_EXECUTABLE )
     # The tests for each config file are independent of whether the