s390/entry: align system call table on 8 bytes

Align system call table on 8 bytes. With sys_call_table entry size
of 8 bytes that eliminates the possibility of a system call pointer
crossing cache line boundary.

Cc: stable@kernel.org
Suggested-by: Ulrich Weigand <ulrich.weigand@de.ibm.com>
Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Sumanth Korikkar <sumanthk@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

arch/s390/kernel/entry.S

@@ -635,6 +635,7 @@ SYM_DATA_START_LOCAL(daton_psw)
 SYM_DATA_END(daton_psw)
 
 	.section .rodata, "a"
+	.balign	8
 #define SYSCALL(esame,emu)	.quad __s390x_ ## esame
 SYM_DATA_START(sys_call_table)
 #include "asm/syscall_table.h"