[S390] cleanup lowcore access from external interrupts

Read external interrupts parameters from the lowcore in the first
level interrupt handler in entry[64].S.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/arch/s390/kernel/smp.c b/arch/s390/kernel/smp.c
index 8127ebd..354589d 100644
--- a/arch/s390/kernel/smp.c
+++ b/arch/s390/kernel/smp.c
@@ -156,7 +156,8 @@
  * cpus are handled.
  */
 
-static void do_ext_call_interrupt(__u16 code)
+static void do_ext_call_interrupt(unsigned int ext_int_code,
+				  unsigned int param32, unsigned long param64)
 {
 	unsigned long bits;