serial: 8250_pci: Implement MSI(-X) support
There may be setups, where legacy interrupts are not available. This is the caese, e.g., when Linux runs as guest (aka. non-root cell) of the partitioning hypervisor Jailhouse. There, only MSI(-X) interrupts are available for guests. But the 8250_pci driver currently only supports legacy ints. So let's enable MSI(-X) interrupts. Nevertheless, this needs to handled with care: while many 8250 devices actually claim to support MSI(-X) interrupts it should not be enabled be default. I had at least one device in my hands with broken MSI implementation. So better introduce a whitelist with devices that are known to support MSI(-X) interrupts. I tested all devices mentioned in the patch. Signed-off-by:Ralf Ramsauer <ralf.ramsauer@oth-regensburg.de> Link: https://lore.kernel.org/r/20190812112152.693622-1-ralf.ramsauer@oth-regensburg.de Signed-off-by: