Revert "printk: add kthread console printers"

Revert "printk: add kthread console printers"

This reverts commit 73ba72e68b17592b6c178f4b7b9e24f0eba32bef.

This reverts commit 077d93bbba82a8a0a3a074fc862b730799e3a5b5.

The testing of 5.19 release candidates revealed missing synchronization
between early and regular console functionality.

It would be possible to start the console kthreads later as a workaround.
But it is clear that console lock serialized console drivers between
each other. It opens a big area of possible problems that were not
considered by people involved in the development and review.

printk() is crucial for debugging kernel issues and console output is
very important part of it. The number of consoles is huge and a proper
review would take some time. As a result it need to be reverted for 5.19.

Link: https://lore.kernel.org/r/YrBdjVwBOVgLfHyb@alley
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20220623145157.21938-6-pmladek@suse.com