* arm_dt: Report OTP SDRAM size via device-tree
Report the SDRAM in gigabits via device-tree as
/proc/device-tree/chosen/rpi-sdram-size-gbit. Scripts reporting the
device-capabilities should use this value (if defined) instead of the
memory-size field in the boardrev row.
* Apply UART_BAUD in early bootsys UART init
Update bootsys and fatal error handlers to use the user
defined UART_BAUD rate.
* rpifwcrypto: Add support for ECDSA P-256 key generation
Also, slightly improve the entropy by passing the system
timer value as the personality string.