net: openthread: Increase stack sizes with FP context
net: openthread: Increase stack sizes with FP context

This PR increases the OpenThread stacks to compensate
for the runtime increase of the MPU stack guard
when the usage of the FP context is detected.

Signed-off-by: Piotr Szkotak <8cc398d5867a9751f66732317e7f1327be1a719f@nordicsemi.no>

finikorg/zephyr,finikorg/zephyr,galak/zephyr,finikorg/zephyr,finikorg/zephyr,zephyrproject-rtos/zephyr,zephyrproject-rtos/zephyr,galak/zephyr,galak/zephyr,zephyrproject-rtos/zephyr,zephyrproject-rtos/zephyr,zephyrproject-rtos/zephyr,galak/zephyr,finikorg/zephyr,galak/zephyr