env: Correct the offset in uboot.

Currently, we set the env partition offset to 320K in MTD partition
table, however the uboot still picks env partition from 256K offset.
This will fix the "erase 0x9f050000 +0x10000" does not erase env
partition issue.

Change-Id: I9c4da6b53bee1b9e37a05f0c32ce2bac05596c24
1 file changed