[PATCH 3/3] sha1-file: change alternate "error:" message to "warning:"

["Ævar Arnfjörð Bjarmason" <avarab@gmail.com>]

Change the "error" message emitted by alt_odb_usable() to be a
"warning" instead. As noted in commits leading up to this one this has
never impacted the exit code ever since the check was initially added
in 26125f6b9b ("detect broken alternates.", 2006-02-22).

It's confusing to emit an "error" when e.g. "git fsck" will exit with
0, so let's emit a "warning:" instead.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
---
 sha1-file.c | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/sha1-file.c b/sha1-file.c
index f142f81658..4b9b63bdcb 100644
--- a/sha1-file.c
+++ b/sha1-file.c
@@ -378,17 +378,17 @@ static int alt_odb_usable(struct raw_object_store *o,
 
 	if (!is_directory(path->buf)) {
 		/* Detect cases where alternate disappeared */
-		error(_("object directory %s does not exist; "
-			"check .git/objects/info/alternates"),
-		      path->buf);
+		warning(_("object directory %s does not exist; "
+			  "check .git/objects/info/alternates"),
+			path->buf);
 		return 0;
 	} else if (is_directory(mkpath("%s/objects", path->buf)) ||
 		   is_directory(mkpath("%s/.git/objects", path->buf))) {
 		/* Detect cases where alternate is a git repository */
-		error(_("object directory %s looks like a git repository; "
-			"alternates must point to the 'objects' directory. "
-			"check .git/objects/info/alternates"),
-		      path->buf);
+		warning(_("object directory %s looks like a git repository; "
+			  "alternates must point to the 'objects' directory. "
+			  "check .git/objects/info/alternates"),
+			path->buf);
 		return 0;
 	}
 
-- 
2.20.0.rc2.403.gdbc3b29805