Add Host support for ch32v20x usbfs

[verylowfreq]

This PR adds HCD for WCH CH32V20x USBFS (USBOTG_FS).

The following issue will be closed:

• support wch ch32v/f full usb host #2613

CH32V20x has two USB peripheral; FSDEV and USBFS. In this PR, USBFS Host driver is enabled when PORT=0 (FSDEV is selected).

I tested on my original CH32V203C8T6 board "Suzuno32RV" (8MHz external crystal, Type-A connector is assigned for USBFS, Type-C connector is for FSDEV).
Please refer for schematic: https://github.com/verylowfreq/board_suzuno32rv

[hathach]

Thank you for your PR, can you pull/merge from master, which include a fix to circleci build.

[verylowfreq]

@hathach Thanks for reply. It seems that my branch is already up-to-date and I couldn't merge more commits. How can I do pull/merge?
My "pr-ch32v-usbfs-host" branch's commits:

[hathach]

sorry, my bad, previous master isn't fix that yet. I have fixed merged and also fixed the pre-commit format as well. It is all good now.

[verylowfreq]

Thank you. I found that the CI failed at macro related problem ("Build / cmake (riscv-gcc)"), so I added commits to solve it.

[hathach]

thank you, I am current working on other stuffs, please give me a bit of time to review this.

[verylowfreq]

@hathach Thank you for sharing your status! I'm preparing to release my Suzuno32RV MCU board, which I used for testing, and I'm also working on porting Adafruit_TinyUSB_Arduino.

My fork of Adafruit_TinyUSB_Arduino:
(Currently, copying ch32v20x_usb.h to arduino_core_ch32 folder is needed to build.)
https://github.com/verylowfreq/Adafruit_TinyUSB_Arduino