[PATCH] nvme: Use pci_iomap instead of ioremap

[Keith Busch]

On Wed, Jan 26, 2022 at 05:33:06PM +0100, Christoph Hellwig wrote:
> pci_iomap goes with the ioread/iowrite accessors which we absolutely
> do not want in nvme.

It looks like the action pci_iomap() uses is based on the
pci_resource_flags(), and should call the same "ioremap()" function we
currently use.

The one problem I see with this, though, is that pci_iomap() will
automatically clamp the mapped length to the resource's length, which
may be shorter than the potential doorbell registers that the driver
thinks it's getting.