aspeed: rainier: Add strap values taken from hardware
When time permits, we should introduce defines for the HW strapping
registers to cleanly decode the values.
SCU500 = 0x00422016
Disable ARM JTAG trusted world debug: 0x1
Disable ARM JTAG debug: 0x1
VGA Memory Size: 0x1 [16MB]
Cortex M3: 0x1 [Disabled]
Boot device: 0x1 [eMMC]
Reserved: 0x1
SCU510 = 0x80000848
Secure Boot Enable: 0x1
Enable boot SPI or eMMC ABR (second boot): 0x1
Enable LPC mode: 0x1 [LPC]
Disable LPC SuperIO 0x2e/0x4e: 0x1
Signed-off-by: Joel Stanley <joel@jms.id.au>
[ clg: rewrote the commit log ]
Signed-off-by: Cédric Le Goater <clg@kaod.org>