[S390] lowcore: Change type of lowcores softirq_pending to __u32.

As noted by akpm:

> kernel/time/tick-sched.c: In function 'tick_nohz_stop_sched_tick':
> kernel/time/tick-sched.c:229: warning: format '%02x' expects type 'unsigned int', but argument 2 has type '__u64'
>
> I don't think the architecture's local_softirq_pending() should return u64.
> This is the sort of thing which should be consistent across architectures.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>

include/asm-s390/lowcore.h

@@ -370,7 +370,8 @@ struct _lowcore
 	__u64        ext_call_fast;            /* 0xdc8 */
 	__u64        percpu_offset;            /* 0xdd0 */
 	__u64        current_task;	       /* 0xdd8 */
-	__u64        softirq_pending;	       /* 0xde0 */
+	__u32	     softirq_pending;	       /* 0xde0 */
+	__u32	     pad_0x0de4;	       /* 0xde4 */
 	__u64        int_clock;                /* 0xde8 */
         __u8         pad12[0xe00-0xdf0];       /* 0xdf0 */