serial: 8250: Dissociate 4MHz Titan ports from Oxford ports

stable inclusion
from stable-v5.10.137
commit 3e9baedb32372aed9b55b3b8a046824df3b0664f
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=3e9baedb32372aed9b55b3b8a046824df3b0664f



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[ Upstream commit f771a34b ]

Oxford Semiconductor PCIe (Tornado) serial port devices have their baud
base set incorrectly, however their `pciserial_board' entries have been
reused for Titan serial port devices.  Define own entries for the latter
devices then, carrying over the settings, so that Oxford entries can be
fixed.

Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
Link: https://lore.kernel.org/r/alpine.DEB.2.21.2106100142310.5469@angie.orcam.me.uk


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>
Reviewed-by: Wei Li <liwei391@huawei.com>