Move files.

src/backend/backend.cmake

@@ -1,12 +1,13 @@
 include (src/backend/cpu/cpu.cmake)
+include (src/backend/common/common.cmake)
 
 
 set(HEADERS_BACKEND
-    "${HEADERS_CPU}"
-    src/backend/Threads.h
+    "${HEADERS_BACKEND_COMMON}"
+    "${HEADERS_BACKEND_CPU}"
    )
 
 set(SOURCES_BACKEND
-    "${SOURCES_CPU}"
-    src/backend/Threads.cpp
+    "${SOURCES_BACKEND_COMMON}"
+    "${SOURCES_BACKEND_CPU}"
    )