If the memory is not iomem we should not try to
ioremap it. Should fix :

https://bugs.freedesktop.org/show_bug.cgi?id=27822Signed-off-by: NJerome Glisse <jglisse@redhat.com>
Tested-by: NRafał Miłecki <zajec5@gmail.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>