[aarch64-port-dev ] Use generic stack banging code for C2

[Andrew Haley]

On 11/14/2013 12:19 PM, Andrew Haley wrote:
>   0x00007fffed198040: movn	xscratch2, #0x8fff
>   0x00007fffed198044: ldr	xzr, [xscratch2,x9]

Argh.

  0x00007fffed198040: movn	xscratch2, #0x8fff
  0x00007fffed198044: ldr	xzr, [sp,xscratch2]