[S390] Convert to SPARSEMEM & SPARSEMEM_VMEMMAP

Convert s390 to SPARSEMEM and SPARSEMEM_VMEMMAP. We do a select
of SPARSEMEM_VMEMMAP since it is configurable. This is because
SPARSEMEM without SPARSEMEM_VMEMMAP gives us a hell of broken
include dependencies that I don't want to fix.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index 8f5f021..29a7940 100644
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -300,6 +300,14 @@
 
 source "kernel/Kconfig.preempt"
 
+config ARCH_SPARSEMEM_ENABLE
+	def_bool y
+	select SPARSEMEM_VMEMMAP_ENABLE
+	select SPARSEMEM_VMEMMAP
+
+config ARCH_SPARSEMEM_DEFAULT
+	def_bool y
+
 source "mm/Kconfig"
 
 comment "I/O subsystem configuration"