[S390] lowcore cleanup

Remove the save_area_64 field from the 0xe00 - 0xf00 area in the lowcore.
Use a free slot in the save_area array instead.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/arch/s390/kernel/entry64.S b/arch/s390/kernel/entry64.S
index 713da07..3257f7f 100644
--- a/arch/s390/kernel/entry64.S
+++ b/arch/s390/kernel/entry64.S
@@ -869,12 +869,12 @@
 # PSW restart interrupt handler
 #
 ENTRY(psw_restart_int_handler)
-	stg	%r15,__LC_SAVE_AREA_64(%r0)	# save r15
+	stg	%r15,__LC_SAVE_AREA+120(%r0)	# save r15
 	larl	%r15,restart_stack		# load restart stack
 	lg	%r15,0(%r15)
 	aghi	%r15,-SP_SIZE			# make room for pt_regs
 	stmg	%r0,%r14,SP_R0(%r15)		# store gprs %r0-%r14 to stack
-	mvc	SP_R15(8,%r15),__LC_SAVE_AREA_64(%r0)# store saved %r15 to stack
+	mvc	SP_R15(8,%r15),__LC_SAVE_AREA+120(%r0)# store saved %r15 to stack
 	mvc	SP_PSW(16,%r15),__LC_RST_OLD_PSW(%r0)# store restart old psw
 	xc	__SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15) # set backchain to 0
 	brasl	%r14,do_restart