dts64: mt7622: disable spi1 and uart2 because pins are used by pwm

MDI_TP_P0 (gpio51) is used by pwm1 and uart2 (uart1 on gpio-header)
MDI_RP_P4 (gpio67) is used by pwm4 and spi1

Signed-off-by: Frank Wunderlich <frank-w@public-files.de>
Link: https://lore.kernel.org/r/20201016204019.2606-3-linux@fw-web.de


Signed-off-by: Matthias Brugger <matthias.bgg@gmail.com>