treewide: replace obsolete _refok by __ref

There was only one use of __initdata_refok and __exit_refok

__init_refok was used 46 times against 82 for __ref.

Those definitions are obsolete since commit 312b1485fb ("Introduce new
section reference annotations tags: __ref, __refdata, __refconst")

This patch removes the following compatibility definitions and replaces
them treewide.

/* compatibility defines */
#define __init_refok     __ref
#define __initdata_refok __refdata
#define __exit_refok     __ref

I can also provide separate patches if necessary.
(One patch per tree and check in 1 month or 2 to remove old definitions)

[akpm@linux-foundation.org: coding-style fixes]
Link: http://lkml.kernel.org/r/1466796271-3043-1-git-send-email-fabf@skynet.be
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/page_alloc.c

@@ -5276,7 +5276,7 @@ void __init setup_per_cpu_pageset(void)
 		setup_zone_pageset(zone);
 }
 
-static noinline __init_refok
+static noinline __ref
 int zone_wait_table_init(struct zone *zone, unsigned long zone_size_pages)
 {
 	int i;
@@ -5903,7 +5903,7 @@ static void __paginginit free_area_init_core(struct pglist_data *pgdat)
 	}
 }
 
-static void __init_refok alloc_node_mem_map(struct pglist_data *pgdat)
+static void __ref alloc_node_mem_map(struct pglist_data *pgdat)
 {
 	unsigned long __maybe_unused start = 0;
 	unsigned long __maybe_unused offset = 0;

mm/slab.c

@@ -1877,7 +1877,7 @@ static struct array_cache __percpu *alloc_kmem_cache_cpus(
 	return cpu_cache;
 }
 
-static int __init_refok setup_cpu_cache(struct kmem_cache *cachep, gfp_t gfp)
+static int __ref setup_cpu_cache(struct kmem_cache *cachep, gfp_t gfp)
 {
 	if (slab_state >= FULL)
 		return enable_cpucache(cachep, gfp);

mm/sparse-vmemmap.c

@@ -36,7 +36,7 @@
  * Uses the main allocators if they are available, else bootmem.
  */
 
-static void * __init_refok __earlyonly_bootmem_alloc(int node,
+static void * __ref __earlyonly_bootmem_alloc(int node,
 				unsigned long size,
 				unsigned long align,
 				unsigned long goal)

mm/sparse.c

@@ -59,7 +59,7 @@ static inline void set_section_nid(unsigned long section_nr, int nid)
 #endif
 
 #ifdef CONFIG_SPARSEMEM_EXTREME
-static struct mem_section noinline __init_refok *sparse_index_alloc(int nid)
+static noinline struct mem_section __ref *sparse_index_alloc(int nid)
 {
 	struct mem_section *section = NULL;
 	unsigned long array_size = SECTIONS_PER_ROOT *