juno/xrp7724: Cache voltage value to save I2C transmissions
Created by: raphaelgault
This patch introduces a cache for the voltage value for each PSU device in order to prevent the device from doing I2C transmissions and reading the voltage if it is already cached or set to the requested value.
Change-Id: I812b2b442069a2f4929d801c79989aea75a265f9 Signed-off-by: Raphael Gault raphael.gault@arm.com