arch: arc: add the support of STACK_SENTINEL

* call the _check_stack_sentinel in unnested isr
return.

* for firq, _check_stack_sentinel is called in kernel
  isr stack because the limitation of banked register

* for normal irq, _check_stak_sentinel is called in
  the interruptted thread stack

Signed-off-by: Wayne Ren <wei.ren@synopsys.com>