[U-Boot] [PATCH] mpc83xx: Make it boot again

[Wood Scott-B07421]

Joakim Tjernlund wrote:
> Trial and error suggests that map_flash_by_law1 needs
> an isync(padding with 4 nop's also did the trick)
> after updating LBLAWAR1 to make sure the the change has
> reached the HW before continuing with the code that depends on it.
> Add an isync to remap_flash_by_law0 for good measure too.

To be totally safe, we probably want to do a readback plus twi (to turn a data dependency into a flow dependency) before the isync.

-Scott