Please apply "ext4: don't allow journal inode to have encrypt flag" to 5.15 and earlier

Please apply commit 105c78e12468 ("ext4: don't allow journal inode to have encrypt flag") to the 5.15, 5.10, 5.4, and 4.19 LTS kernels, where it applies cleanly.

It didn't get applied automatically because for the Fixes tag, I used a commit in 5.18. However, that was the commit that exposed the problem, not the root cause. IMO it makes sense to apply this to earlier kernels too, especially because some people have backported the 5.18 commit.

- Eric