fsck.c: give "FOREACH_MSG_ID" a more specific name

Rename the FOREACH_MSG_ID macro to FOREACH_FSCK_MSG_ID in preparation
for moving it over to fsck.h. It's good convention to name macros
in *.h files in such a way as to clearly not clash with any other
names in other files.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

fsck.c

diff --git a/fsck.c b/fsck.c
index 1b12e82..31c9088 100644
--- a/fsck.c
+++ b/fsck.c
@@ -22,7 +22,7 @@
 static struct oidset gitmodules_found = OIDSET_INIT;
 static struct oidset gitmodules_done = OIDSET_INIT;
 
-#define FOREACH_MSG_ID(FUNC) \
+#define FOREACH_FSCK_MSG_ID(FUNC) \
 	/* fatal errors */ \
 	FUNC(NUL_IN_HEADER, FATAL) \
 	FUNC(UNTERMINATED_HEADER, FATAL) \
@@ -83,7 +83,7 @@ static struct oidset gitmodules_done = OIDSET_INIT;
 
 #define MSG_ID(id, msg_type) FSCK_MSG_##id,
 enum fsck_msg_id {
-	FOREACH_MSG_ID(MSG_ID)
+	FOREACH_FSCK_MSG_ID(MSG_ID)
 	FSCK_MSG_MAX
 };
 #undef MSG_ID
@@ -96,7 +96,7 @@ static struct {
 	const char *camelcased;
 	enum fsck_msg_type msg_type;
 } msg_id_info[FSCK_MSG_MAX + 1] = {
-	FOREACH_MSG_ID(MSG_ID)
+	FOREACH_FSCK_MSG_ID(MSG_ID)
 	{ NULL, NULL, NULL, -1 }
 };
 #undef MSG_ID