[IA64] CONFIG_KEXEC/CONFIG_CRASH_DUMP permutations

Actually, on reflection I think that there is a good case for
keeping the options separate. I am thinking particularly of people
who want a very small crashdump kernel and thus don't want to compile
in kexec.

The patch below should fix things up so that all valid combinations of
KEXEC, CRASH_DUMP and VMCORE compile cleanly - VMCORE depends on
CRASH_DUMP which is why I said valid combinations. In a nutshell
it just untangles unrelated code and switches around a few defines.

Please note that it creats a new file, arch/ia64/kernel/crash_dump.c
This is in keeping with the i386 implementation.

Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Tony Luck <tony.luck@intel.com>

arch/ia64/kernel/smp.c

@@ -157,7 +157,7 @@ handle_IPI (int irq, void *dev_id)
 			      case IPI_CPU_STOP:
 				stop_this_cpu();
 				break;
-#ifdef CONFIG_CRASH_DUMP
+#ifdef CONFIG_KEXEC
 			      case IPI_KDUMP_CPU_STOP:
 				unw_init_running(kdump_cpu_freeze, NULL);
 				break;
@@ -219,7 +219,7 @@ send_IPI_self (int op)
 	send_IPI_single(smp_processor_id(), op);
 }
 
-#ifdef CONFIG_CRASH_DUMP
+#ifdef CONFIG_KEXEC
 void
 kdump_smp_send_stop()
 {