[S390] Get rid of a lot of sparse warnings.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/include/asm-s390/setup.h b/include/asm-s390/setup.h
index 9574fe8..5427697 100644
--- a/include/asm-s390/setup.h
+++ b/include/asm-s390/setup.h
@@ -74,6 +74,9 @@
 extern unsigned int console_devno;
 extern unsigned int console_irq;
 
+extern char vmhalt_cmd[];
+extern char vmpoff_cmd[];
+
 #define CONSOLE_IS_UNDEFINED	(console_mode == 0)
 #define CONSOLE_IS_SCLP		(console_mode == 1)
 #define CONSOLE_IS_3215		(console_mode == 2)