83xx, kmeter1, fix: update in the DTS the correct size for the first flash

When updating the "reg" in the "/localbus/flash@f0000000,0" node
size was wrong updated for the first flash, because the total
size was filled in, instead of the right size for it.

Signed-off-by: Heiko Schocher <hs@denx.de>
Signed-off-by: Kim Phillips <kim.phillips@freescale.com>