Implement protection against the stack clash attack  through inline stack probing.
Probe stack allocation every PAGE_SIZE during frame lowering or dynamic allocation to make sure the page guard, if any, is touched when touching the stack, in a similar manner to GCC.
This extends the existing probe-stack mechanism with a special value inline-asm. Technically the former uses function call before stack allocation while this patch provides inlined stack probes and chunk allocation.
Only implemented for x86.