Install CH552 support for platformio (and CH5xx variants) with ch5xduino support

https://community.platformio.org/t/platformio-8051-model-medium-linker-err/18099

''

mkdir ~/.platformio/boards

cd ~/.platformio/boards

cat > ch55xduino.json << 'EOF'

{

  "build": {    

    "f_cpu": "24000000",

    "size_iram": 256,

    "size_xram": 1024,

    "size_code": 14336,

    "size_heap": 128,

    "mcu": "ch552t",

    "cpu": "mcs51"

  },

  "frameworks": [],

  "upload": {

    "maximum_ram_size": 1280,

    "maximum_size": 14336,

    "protocol": "stcgal",

    "stcgal_protocol": "stc15",

    "protocols": [

      "stcgal"

    ]

  },

  "name": "Generic CH552",

  "url": "http://www.wch.cn/product/CH552.html",

  "vendor": "WCH"

}

EOF

platformio boards|grep ch5xduino

cd

mkdir myproj552

cd myproj552

platformio init --board ch55xduino

cat > platformio.ini <<'EOF'

[env:ch552]

platform = intel_mcs51

board = ch552

build_flags =

  --model-medium

  --LC:/Users/caoyf/.platformio/packages/toolchain-sdcc/lib/medium

  -IC:

  -IC:/Users/caoyf/Documents/PlatformIO/Projects/ch552_gpio/src/Driver/inc

  -Isrc/PLAT/inc

extra_scripts = link_medium.py
'EOF'

cat > link_medium.py

Import("env")

env.Append(LINKFLAGS=["--model-medium"])

''