This commit updates the documentation as follows:
- stresses that the lazy stacking preservation is disabled
by default and not supported in ARM Cortex-M builds,
- corrects the figure of extra stack requirement when
floating point services are enabled in ARM builds.
Signed-off-by: Ioannis Glaropoulos <Ioannis.Glaropoulos@nordicsemi.no>
3bc0f88653