ARM: mvebu: clearfog: read basic TLV data

Read RAM die capacity from the EEPROM TLV.

Follow the ONIE standard that defines the Vendor Extension entry type
for vendor specific data. We have no Private Enterprise Number at the
moment as the standard requires. Use the dummy all 0xff value for now.

Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Reviewed-by: Stefan Roese <sr@denx.de>