USB: serial: fix tty-port initialized comments

stable inclusion
from stable-v5.10.137
commit a916e8036079eec97762589ac2ab8b95dca50ea8
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I60PLB

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=a916e8036079eec97762589ac2ab8b95dca50ea8



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[ Upstream commit 688ee1d1 ]

Fix up the tty-port initialized comments which got truncated and
obfuscated when replacing the old ASYNCB_INITIALIZED flag.

Fixes: d41861ca ("tty: Replace ASYNC_INITIALIZED bit and update atomically")
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>
Reviewed-by: Wei Li <liwei391@huawei.com>