ARM: dts: aspeed: rainier: Fix i2c eeprom size

Fix the size of the Proc VRM card's eeprom used for vpd storage. The
size is changed from 64Kbit to 128Kbit.

Signed-off-by: Jinu Joy Thomas <jinu.joy.thomas@in.ibm.com>
Reviewed-by: Santosh Puranik <santosh.puranik.ibm@gmail.com>
Signed-off-by: Joel Stanley <joel@jms.id.au>