Allow different port and mode for LED on ch32v boards

[deshipu]

While there is a define for the port, the clock enable is hardcoded for GPIOA, so setting a different port than GPIOA doesn't work. This fixes it by adding a define for enabling the port clock.

It also adds a define for the pin mode, because not all boards have the LED connected in a way that open drain works with it.

[HiFiPhile]

Thank you for the PR, I think you missed APB1 and APB2.

CI failed with:

In file included from /home/circleci/project/hw/bsp/ch32v20x/family.c:21:
/home/circleci/project/hw/bsp/ch32v20x/family.c: In function 'board_init':
/home/circleci/project/hw/bsp/ch32v20x/boards/nanoch32v203/board.h:16:47: error: 'RCC_APB1Periph_GPIOA' undeclared (first use in this function); did you mean 'RCC_APB2Periph_GPIOA'?
   16 | #define LED_CLOCK_EN() RCC_APB1PeriphClockCmd(RCC_APB1Periph_GPIOA, ENABLE)
      |                                               ^~~~~~~~~~~~~~~~~~~~
/home/circleci/project/hw/bsp/ch32v20x/family.c:99:3: note: in expansion of macro 'LED_CLOCK_EN'
   99 |   LED_CLOCK_EN();
      |   ^~~~~~~~~~~~
compilation terminated due to -Wfatal-errors.

[deshipu]

You are right, I'm sorry I didn't notice it. I only tested it on my own board that has the LED on port C, which is APB2. I'll fix it immediately.