kconfig: Have the 'SMP' option depend on 'USE_SWITCH'
kconfig: Have the 'SMP' option depend on 'USE_SWITCH'

SMP requires the new-style '_arch_switch' to be enabled. To prevent
users from creating invalid configurations where SMP is enabled while
_arch_switch is not, we add a dependency from SMP to USE_SWITCH.

Signed-off-by: Sebastian Bøe <edee888afd63e94916688495334700803eba20a0@nordicsemi.no>

zephyrproject-rtos/zephyr,Vudentz/zephyr,nashif/zephyr,zephyrproject-rtos/zephyr,GiulianoFranchetto/zephyr,finikorg/zephyr,GiulianoFranchetto/zephyr,galak/zephyr,nashif/zephyr,nashif/zephyr,punitvara/zephyr,nashif/zephyr,galak/zephyr,finikorg/zephyr,zephyrproject-rtos/zephyr,finikorg/zephyr,GiulianoFranchetto/zephyr,explora26/zephyr,finikorg/zephyr,explora26/zephyr,ldts/zephyr,explora26/zephyr,ldts/zephyr,zephyrproject-rtos/zephyr,Vudentz/zephyr,galak/zephyr,Vudentz/zephyr,nashif/zephyr,GiulianoFranchetto/zephyr,Vudentz/zephyr,ldts/zephyr,GiulianoFranchetto/zephyr,galak/zephyr,ldts/zephyr,punitvara/zephyr,finikorg/zephyr,punitvara/zephyr,punitvara/zephyr,Vudentz/zephyr,punitvara/zephyr,zephyrproject-rtos/zephyr,Vudentz/zephyr,explora26/zephyr,ldts/zephyr,explora26/zephyr,galak/zephyr