kernel: smp: avoid identifier collisions
kernel: smp: avoid identifier collisions

MISRA-C Rule 5.3 states that identifiers in inner scope should
not hide identifiers in outer scope.

In the function smp_init_top(), the variable "start_flags"
collide with global variable of the same name. So rename the one
inside the function.

Signed-off-by: Daniel Leung <d94e04d205b5962d7873a139ef298b03c1717f72@intel.com>

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