Add translation files only if the NLS knob is set

--- src/CMakeLists.txt.orig	2019-12-05 06:33:57 UTC
+++ src/CMakeLists.txt
@@ -287,7 +287,9 @@ target_compile_definitions(Mapper_Common INTERFACE
 )
 
 
-mapper_translations_sources(${Mapper_Common_SRCS} ${Mapper_Common_HEADERS})
+if(Mapper_WITH_NLS)
+	mapper_translations_sources(${Mapper_Common_SRCS} ${Mapper_Common_HEADERS})
+endif()
 
 
 # Mapper executable
