s390/mm: keep fault_init() private to fault.c

Just convert fault_init() to an early initcall. That's still early
enough since it only needs be called before user space processes get
executed. No reason to externalize it.
Also add the function to the init section and move the store_indication
variable to the read_mostly section.

Signed-off-by: Heiko Carstens <[e-mail]>
Signed-off-by: Martin Schwidefsky <[e-mail]>

arch/s390/include/asm/pgtable.h

···
 extern pgd_t swapper_pg_dir[] __attribute__ ((aligned (4096)));
 extern void paging_init(void);
 extern void vmem_map_init(void);
-extern void fault_init(void);
 
 /*
  * The S390 doesn't have any external MMU info: the kernel page

arch/s390/mm/fault.c

···
 #define VM_FAULT_BADCONTEXT	0x010000
 #define VM_FAULT_BADMAP		0x020000
 #define VM_FAULT_BADACCESS	0x040000
-#define VM_FAULT_SIGNAL	0x080000
+#define VM_FAULT_SIGNAL		0x080000
 
-static unsigned long store_indication;
+static unsigned long store_indication __read_mostly;
 
-void fault_init(void)
+#ifdef CONFIG_64BIT
+static int __init fault_init(void)
 {
-	if (test_facility(2) && test_facility(75))
+	if (test_facility(75))
 		store_indication = 0xc00;
+	return 0;
 }
+early_initcall(fault_init);
+#endif
 
 static inline int notify_page_fault(struct pt_regs *regs)
 {

arch/s390/mm/init.c

···
 	max_zone_pfns[ZONE_DMA] = PFN_DOWN(MAX_DMA_ADDRESS);
 	max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
 	free_area_init_nodes(max_zone_pfns);
-	fault_init();
 }
 
 void __init mem_init(void)