sha1_file: move comment about return value where it belongs

Commit 5b08640 (sha1_object_info_extended: make type calculation
optional, Jul 12 2013) changed the return value of the
sha1_object_info_extended function to 0/-1 for success/error.

Previously this function returned the object type for success or
-1 for error. But unfortunately the above commit forgot to change
or move the comment above this function that says "returns enum
object_type or negative".

To fix this inconsistency, let's move the comment above the
sha1_object_info function where it is still true.

Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Author: chriscool

sha1_file.c

@@ -2444,7 +2444,6 @@ static int sha1_loose_object_info(const unsigned char *sha1,
 	return 0;
 }
 
-/* returns enum object_type or negative */
 int sha1_object_info_extended(const unsigned char *sha1, struct object_info *oi)
 {
 	struct cached_object *co;
@@ -2493,6 +2492,7 @@ int sha1_object_info_extended(const unsigned char *sha1, struct object_info *oi)
 	return 0;
 }
 
+/* returns enum object_type or negative */
 int sha1_object_info(const unsigned char *sha1, unsigned long *sizep)
 {
 	enum object_type type;