sha1_file: make read_info_alternates static

read_info_alternates is not used from outside, so let's make it static.

We have to declare the function before link_alt_odb_entry instead of
moving the code around, link_alt_odb_entry calls read_info_alternates,
which in turn calls link_alt_odb_entry.

Signed-off-by: Stefan Beller <sbeller@google.com>
Reviewed-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

cache.h

@@ -1387,7 +1387,6 @@ extern struct alternate_object_database {
 	char base[FLEX_ARRAY]; /* more */
 } *alt_odb_list;
 extern void prepare_alt_odb(void);
-extern void read_info_alternates(const char * relative_base, int depth);
 extern char *compute_alternate_path(const char *path, struct strbuf *err);
 typedef int alt_odb_fn(struct alternate_object_database *, void *);
 extern int foreach_alt_odb(alt_odb_fn, void*);

sha1_file.c

@@ -279,6 +279,7 @@ static int alt_odb_usable(struct strbuf *path, const char *normalized_objdir)
  * SHA1, an extra slash for the first level indirection, and the
  * terminating NUL.
  */
+static void read_info_alternates(const char * relative_base, int depth);
 static int link_alt_odb_entry(const char *entry, const char *relative_base,
 	int depth, const char *normalized_objdir)
 {
@@ -369,7 +370,7 @@ static void link_alt_odb_entries(const char *alt, int len, int sep,
 	strbuf_release(&objdirbuf);
 }
 
-void read_info_alternates(const char * relative_base, int depth)
+static void read_info_alternates(const char * relative_base, int depth)
 {
 	char *map;
 	size_t mapsz;