drivers: flash: flash_simulator: added max len param
drivers: flash: flash_simulator: added max len param

Added a new runtime parameter to the Flash Simulator. It can be used to
ignore part of the data that is written to the simulated flash memory.
This parameter works together with max write calls parameter.

Signed-off-by: Kamil Piszczek <94a00d4c21e2b5f86e16c4df4b1ac94e543626d8@nordicsemi.no>

GiulianoFranchetto/zephyr,nashif/zephyr,finikorg/zephyr,galak/zephyr,galak/zephyr,GiulianoFranchetto/zephyr,Vudentz/zephyr,galak/zephyr,Vudentz/zephyr,finikorg/zephyr,Vudentz/zephyr,finikorg/zephyr,finikorg/zephyr,Vudentz/zephyr,Vudentz/zephyr,zephyrproject-rtos/zephyr,finikorg/zephyr,GiulianoFranchetto/zephyr,nashif/zephyr,nashif/zephyr,nashif/zephyr,GiulianoFranchetto/zephyr,GiulianoFranchetto/zephyr,galak/zephyr,zephyrproject-rtos/zephyr,nashif/zephyr,zephyrproject-rtos/zephyr,galak/zephyr,Vudentz/zephyr,zephyrproject-rtos/zephyr,zephyrproject-rtos/zephyr