serial: 8250_mid: Balance reference count for PCI DMA device

stable inclusion
from stable-v5.10.110
commit 0aebb3944ab1a4f74f3e3e4427f0eb5837d3489c
bugzilla: https://gitee.com/openeuler/kernel/issues/I574AL

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=0aebb3944ab1a4f74f3e3e4427f0eb5837d3489c



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[ Upstream commit 67ec6dd0 ]

The pci_get_slot() increases its reference count, the caller
must decrement the reference count by calling pci_dev_put().

Fixes: 90b9aacf ("serial: 8250_pci: add Intel Tangier support")
Fixes: f549e94e ("serial: 8250_pci: add Intel Penwell ports")
Reported-by: Qing Wang <wangqing@vivo.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Depends-on: d9eda9ba ("serial: 8250_pci: Intel MID UART support to its own driver")
Link: https://lore.kernel.org/r/20220215100920.41984-1-andriy.shevchenko@linux.intel.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Yu Liao <liaoyu15@huawei.com>
Reviewed-by: Wei Li <liwei391@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>