[ARM] clean up a load of old declarations

... some of which are now in linux/*.h headers.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/mm/mm.h b/arch/arm/mm/mm.h
index 7647c59..9659010 100644
--- a/arch/arm/mm/mm.h
+++ b/arch/arm/mm/mm.h
@@ -35,3 +35,5 @@
 void __init create_mapping(struct map_desc *md);
 void __init bootmem_init(struct meminfo *mi);
 void reserve_node_zero(struct pglist_data *pgdat);
+
+extern void _text, _stext, _etext, __data_start, _end, __init_begin, __init_end;