[bsp/hpm6750evk]Remove cherryusb_port.c from SConscript

bsp/hpmicro/hpm6750evk/board/SConscript

@@ -8,7 +8,6 @@ src = Split("""
     rtt_board.c
     pinmux.c
     fal_flash_port.c
-    cherryusb_port.c
     hpm_sgtl5000.c
 """)