add usb serial for hw l412 test

Author: hathach

.github/workflows/build_iar.yml

@@ -93,7 +93,7 @@ jobs:
           echo >> flash.sh 'echo r >> flash.jlink'
           echo >> flash.sh 'echo go >> flash.jlink'
           echo >> flash.sh 'echo exit >> flash.jlink'
-          echo >> flash.sh 'cmdout=$(JLinkExe -device stm32l412kb -if swd -JTAGConf -1,-1 -speed auto -NoGui 1 -ExitOnError 1 -CommandFile flash.jlink)'
+          echo >> flash.sh 'cmdout=$(JLinkExe -USB 774470029 -device stm32l412kb -if swd -JTAGConf -1,-1 -speed auto -NoGui 1 -ExitOnError 1 -CommandFile flash.jlink)'
           echo >> flash.sh 'if (( $? )) ; then echo $cmdout ; fi'
           chmod +x flash.sh