Vita: add SDL_GetPreferredLocales support

CMakeLists.txt

@@ -2279,6 +2279,11 @@ elseif(VITA)
       ${SDL2_SOURCE_DIR}/src/thread/generic/SDL_systls.c)
     set(HAVE_SDL_THREADS TRUE)
   endif()
+  if(SDL_LOCALE)
+    file(GLOB LOCALE_SOURCES ${SDL2_SOURCE_DIR}/src/locale/vita/*.c)
+    set(SOURCE_FILES ${SOURCE_FILES} ${LOCALE_SOURCES})
+    set(HAVE_SDL_LOCALE TRUE)
+  endif()
   if(SDL_TIMERS)
     set(SDL_TIMER_VITA 1)
     file(GLOB TIMER_SOURCES ${SDL2_SOURCE_DIR}/src/timer/vita/*.c)