[U-Boot] [U-Boot, v2] Enable expression support for CONFIG_BOARD_SIZE_LIMIT

[Martin Husemann]

On Fri, Mar 08, 2019 at 12:17:09PM -0500, Tom Rini wrote:
> OK, so a few thoughts here.
> - What's the portable way to do hex-based math?  If we really need it?

Use printf(3) to convert to/from hex, and standard shell arithmetic
with $(( )).

Looks horrible, but something like:

v=$(( $( printf "%d\n" 0xa0 ) + $( printf "%d\n" 0x10 ) ))
printf "v = %d (%x)\n" $v $v


... maybe arranged into some sh helper functions.

Martin