CMake: Add install target

Do **not** use this with /usr or /usr/local. It creates subdirectories
for resources/translations in the install prefix.

It's intended for creating a relocatable, self-contained bundle, which
can be packaged.

src/core/CMakeLists.txt

@@ -214,4 +214,8 @@ function(add_core_resources target)
     endif()
     add_resources(${target} ${path} ${CMAKE_SOURCE_DIR}/data/resources/)
   endforeach()
+  if(ALLOW_INSTALL)
+    install_imported_dep_library(cpuinfo::cpuinfo)
+    install(DIRECTORY "$<TARGET_FILE_DIR:${target}>/resources" DESTINATION "${CMAKE_INSTALL_PREFIX}")
+  endif()
 endfunction()