[S390] Enable kmemleak on s390.

Also increase the maximum possible kmemleak early log entries since
2000 are not sufficient on s390.

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/vmlinux.lds.S b/arch/s390/kernel/vmlinux.lds.S
index bc15ef9..a68ac10 100644
--- a/arch/s390/kernel/vmlinux.lds.S
+++ b/arch/s390/kernel/vmlinux.lds.S
@@ -51,6 +51,7 @@
 
 	. = ALIGN(PAGE_SIZE);
 	_eshared = .;		/* End of shareable data */
+	_sdata = .;		/* Start of data section */
 
 	EXCEPTION_TABLE(16) :data