BPI-CM4: Add support for the waveshare cm4-io-base-b
https://www.waveshare.com/wiki/CM4-IO-BASE-B
BPI-CM4: Enable usb support on waveshare baseboards via overlay
BPI-SM1: Removed UART_B overlay. Short of it being an available
option in the vendor kernel via overlay. I can not find any docs
to support why that is. I feel it is safer that we just remove it.
BPI-SM1: Add UART_A "pin-ctrl: cts rts"
Signed-off-by: Patrick Yavitz <pyavitz@xxxxx.com>
