s390/kexec: move machine_crash_shutdown() to machine_kexec.c

machine_crash_shutdown() was the only function in crash.c.
So move the function and delete one file.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/arch/s390/kernel/machine_kexec.c b/arch/s390/kernel/machine_kexec.c
index 493304b..0d5063e0 100644
--- a/arch/s390/kernel/machine_kexec.c
+++ b/arch/s390/kernel/machine_kexec.c
@@ -191,6 +191,10 @@
 {
 }
 
+void machine_crash_shutdown(struct pt_regs *regs)
+{
+}
+
 /*
  * Do normal kexec
  */