Do not block the boot process for five seconds or longer. When
adding the configurable timeout the other timeout code got broken.
Remove it and instead supply uart_recv_bytes with the timeout per
Instead of counting a variable sleep for a given/predictable time.
Update the uart code with this value.
Add the sysmobts_v2 board, move the DDR type detection into the ubl
with a fallback for the sysmobts_v1 with the current type of ram.