MMC pin reassigment
- Making it easier for reprogramming using USB UART:
> * Merge USB UART with Programming uart to be able
> * Connect USB_DTR_DSR to MMC BOOT line via switch
> * Connect USB_RTS_CTS to MMC RESET line via switch- Move TCLK_A_C_SEL to Pin 82 (old TXD)
- Move EN_RTM_PWR to pin 85 (old RXD)
- USE pin 21 to measure V12 input voltage with potential divider.