char/mwave: remove printk tracing

The printk tracing makes the code hard to follow for no good benefit.
Everyone can use dynamic tracing and/or kprobes.

Drop this unreadable bloatware too.

Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://patch.msgid.link/20251119091949.825958-5-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Author: Jiri Slaby (SUSE)