Revert "Add tile constraint to loopfilter mask fix-up code"

This reverts commit 6fa9df9c. The
behaviour shown there only happens when show_existing_frame=1, i.e.
it was the same bug as 2e991b14.
8 jobs for master in 3 minutes and 30 seconds (queued for 1 second)
Status Name Job ID Coverage
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passed build-debian-werror #5299
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