This commit enabled TEST_USERSPACE_WITHOUT_HW_STACK_PROTECTION
Kconfig option by default for ke1xf SoC Series, which instructs
the build to disable HW stack protection from tests that are to
run with User Mode enabled. This is done because this platform
does not have a sufficient number of MPU regions to support HW
stack protection (Stack Guards) and User Mode simultaneously.
Signed-off-by: Ioannis Glaropoulos <Ioannis.Glaropoulos@nordicsemi.no>