BugLink: http://bugs.launchpad.net/bugs/1559609

Split dma resource allocation and io register assignment from get_config
to a new function arcmsr_alloc_io_queue.
Signed-off-by: Ching Huang <ching2048@areca.com.tw>
Reviewed-by: Tomas Henzl <thenzl@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
(cherry picked from commit 02040670)
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>