jdb2: replace remaining __FUNCTION__ occurrences

__FUNCTION__ is gcc-specific, use __func__

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Cc: <linux-ext4@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

fs/jbd2/revoke.c

@@ -139,7 +139,7 @@ repeat:
 oom:
 	if (!journal_oom_retry)
 		return -ENOMEM;
-	jbd_debug(1, "ENOMEM in %s, retrying\n", __FUNCTION__);
+	jbd_debug(1, "ENOMEM in %s, retrying\n", __func__);
 	yield();
 	goto repeat;
 }