MikroTik CRS305-1G-4S Bit board has a switch chip with an integrated Marvell Prestera 98DX3236 CPU. The Bit board variant is added, which has a bigger Macronix flash. Add basic U-Boot, UART and Winbond SPI flash support. Signed-off-by: Luka Kovacic <luka.kovacic@sartura.hr> Cc: Luka Perkov <luka.perkov@sartura.hr> Cc: Jakov Petrina <jakov.petrina@sartura.hr> Reviewed-by: Stefan Roese <sr@denx.de>