docs: Change name of padding arguments
docs: Change name of padding arguments

To be squashed

Signed-off-by: David Brown <0af22db655f3ade5845314d695c1f4910314b0cb@linaro.org>

runtimeco/mcuboot,ATmobica/mcuboot,runtimeco/mcuboot,tamban01/mcuboot,runtimeco/mcuboot,utzig/mcuboot,runtimeco/mcuboot,tamban01/mcuboot,utzig/mcuboot,utzig/mcuboot,ATmobica/mcuboot,utzig/mcuboot,ATmobica/mcuboot,utzig/mcuboot,tamban01/mcuboot,tamban01/mcuboot,tamban01/mcuboot,ATmobica/mcuboot,ATmobica/mcuboot,runtimeco/mcuboot