moves tx_timer interrupt into port

as this is not moonlight specific, it should not be placed in such a way

CMakeLists.txt

@@ -43,7 +43,6 @@ function(setup_target TARGET)
           port/moonlight/trap_non_vectored.c
           port/moonlight/exception.c
           port/moonlight/vector_table.c
-          port/moonlight/tx_timer_interrupt.c
   )
   if("netxduo" IN_LIST ST_LIBRARIES)
     target_sources(${TARGET} PRIVATE port/moonlight/mnrs_network_driver.c)

port/threadx/CMakeLists.txt

@@ -9,8 +9,7 @@ target_sources(${PROJECT_NAME}
     ${CMAKE_CURRENT_LIST_DIR}/src/tx_thread_schedule.S
     ${CMAKE_CURRENT_LIST_DIR}/src/tx_thread_stack_build.S
     ${CMAKE_CURRENT_LIST_DIR}/src/tx_thread_system_return.S
-    #${CMAKE_CURRENT_LIST_DIR}/src/tx_timer_interrupt.c
+    ${CMAKE_CURRENT_LIST_DIR}/src/tx_timer_interrupt.c
-    #${CMAKE_CURRENT_LIST_DIR}/src/platform_rand.c
     # {{END_TARGET_SOURCES}}
 )