moved stacktrace to sysctl, as vmctl is very privileged so can't

be used outside VM. IS code cleanup. added stacktrace feature to IS.

lib/syslib/sys_sysctl.c

@@ -12,3 +12,9 @@ PUBLIC int sys_sysctl(int code, char *arg1, int arg2)
   return(_taskcall(SYSTASK, SYS_SYSCTL, &m));
 
 }
+
+PUBLIC int sys_sysctl_stacktrace(endpoint_t ep)
+{
+  return sys_sysctl(SYSCTL_CODE_STACKTRACE, NULL, ep);
+}
+