[S390] hardirq: remove pointless header file includes

Remove a couple of pointless header file includes.
Fixes a compile bug caused by header file include dependencies with
"irq: Add tracepoint to softirq_raise" within linux-next.

Reported-by: Sachin Sant <sachinp@in.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
[ cherry-picked from the s390 tree to fix "2bf2160d: irq: Add tracepoint to softirq_raise" ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>