[Toybox] FYI, devmem change

[Rob Landley]

Heads up, output of devmem is now decimal if you gave it a decimal address and
hexadecimal if you gave it a 0xhecidecimal address. Meaning the default output
type changed from hex to decimal, since it never accepted hex addresses before.

(Also, it consistently says 0x for hex output, instead of not saying 0x at the
front of zero output. I have no idea why the gnu/dammit # extension does that
but it's creepy.)

Possibly I should pad hex output to the number of bytes requested so it displays
consistently. :)

Rob