Support log over USB serial

[HaoboGu]

No description provided.

[HaoboGu]

Known issue: the logger requires USB connection, using USB logger makes it quite complex when switching between USB and BLE.

One solution is to run the usb logger + keyboard whenever the USB is connection, but if the communication type is set to BLE, the report won't be sent to the USB reporter. Though, this needs the architecture update, which will be done later. So this PR now blocks.

[github-actions]

PR build size

  text	   data	    bss	    dec	    hex	filename
124252	    116	  41308	 165676	  2872c	rmk-nrf52840

Diff

    FILE SIZE        VM SIZE    
 --------------  -------------- 
  +1.4% +2.76Ki  [ = ]       0    .debug_loc
  +0.1% +1.53Ki  [ = ]       0    .debug_str
  +0.1%    +948  [ = ]       0    .debug_info
  +0.4%    +499  [ = ]       0    .debug_line
  +0.3%    +432  [ = ]       0    .strtab
  +0.1%    +152  [ = ]       0    .debug_ranges
  +0.4%     +72  [ = ]       0    .debug_aranges
  +0.1%     +32  [ = ]       0    .symtab
  +0.6%      +3  [ = ]       0    .defmt
  -5.9%      -4  [ = ]       0    [Unmapped]
  -0.1%      -6  [ = ]       0    .debug_abbrev
  -0.2%     -32  [ = ]       0    .debug_frame
  -1.1%    -184  -1.1%    -184    .rodata
  -0.2%    -200  -0.2%    -200    .text
  +0.2% +5.96Ki  -0.2%    -384    TOTAL

[HaoboGu]

I'll split this PR to two, the first adds defmt feature and the second adds usb logger.