s390/setup: do not reserve the decompressor code

Introduce PARMAREA_END, and use it for memblock reserve of low
memory, which is used for lowcore, kdump data mover code and page
buffer, early stack and parmarea. There is no need to reserve an
area between PARMAREA_END and the decompressor _ehead.

Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/arch/s390/include/asm/setup.h b/arch/s390/include/asm/setup.h
index 9c30ebe..be02f05 100644
--- a/arch/s390/include/asm/setup.h
+++ b/arch/s390/include/asm/setup.h
@@ -11,6 +11,7 @@
 
 
 #define PARMAREA		0x10400
+#define PARMAREA_END		0x11000
 
 /*
  * Machine features detected in early.c