jbd2: remove pointless assertion in __journal_remove_journal_head

Only when jh->b_jcount = 0 in jbd2_journal_put_journal_head, we are allowed
to call __journal_remove_journal_head. This assertion is meaningless,
just remove it.
Signed-off-by: Shijie Luo <luoshijie1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20200123070054.50585-1-luoshijie1@huawei.comSigned-off-by: Theodore Ts'o <tytso@mit.edu>

fs/jbd2/journal.c

@@ -2560,7 +2560,6 @@ static void __journal_remove_journal_head(struct buffer_head *bh)
 {
 	struct journal_head *jh = bh2jh(bh);
 
-	J_ASSERT_JH(jh, jh->b_jcount >= 0);
 	J_ASSERT_JH(jh, jh->b_transaction == NULL);
 	J_ASSERT_JH(jh, jh->b_next_transaction == NULL);
 	J_ASSERT_JH(jh, jh->b_cp_transaction == NULL);