mm: fix section mismatch warnings

modpost had two cases hardcoded for mm/
Shift over to __init_refok and kill the
hardcoded function names in modpost.

This has the drawback that the functions
will always be kept no matter configuration.
With previous code the function were placed in
init section if configuration allowed it.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
diff --git a/mm/sparse.c b/mm/sparse.c
index 6f3fff9..1302f834 100644
--- a/mm/sparse.c
+++ b/mm/sparse.c
@@ -44,7 +44,7 @@
 #endif
 
 #ifdef CONFIG_SPARSEMEM_EXTREME
-static struct mem_section noinline *sparse_index_alloc(int nid)
+static struct mem_section noinline __init_refok *sparse_index_alloc(int nid)
 {
 	struct mem_section *section = NULL;
 	unsigned long array_size = SECTIONS_PER_ROOT *