[S390] Remove config options.

On s390 we always want to run with precise cputime accounting.
Remove the config options VIRT_TIMER and VIRT_CPU_ACCOUNTING.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/arch/s390/kernel/time.c b/arch/s390/kernel/time.c
index 4965285..9562029 100644
--- a/arch/s390/kernel/time.c
+++ b/arch/s390/kernel/time.c
@@ -286,10 +286,8 @@
 
 	/* Enable TOD clock interrupts on the boot cpu. */
 	init_cpu_timer();
-
-#ifdef CONFIG_VIRT_TIMER
+	/* Enable cpu timer interrupts on the boot cpu. */
 	vtime_init();
-#endif
 }
 
 /*