socrates: fix SPD EEPROM address

Commit be0bd8234b9777ecd63c4c686f72af070d886517
changed SPD EEPROM address to 0x51 and DDR SDRAM
detection stopped working. Change this address
back to 0x50.

Signed-off-by: Anatolij Gustschin <agust@denx.de>
1 file changed