Don't open-code the OpenFirmware "dcr-reg" property lookup trying to map
DCR resources.  This makes the code a bit easier to read.
Signed-off-by: Kyle Moffett <Kyle.D.Moffett@boeing.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
                          struct mpic_reg_bank *rb,
                          unsigned int offset, unsigned int size)
 {
-       const u32 *dbasep;
-
-       dbasep = of_get_property(node, "dcr-reg", NULL);
-
-       rb->dhost = dcr_map(node, *dbasep + offset, size);
+       phys_addr_t phys_addr = dcr_resource_start(node, 0);
+       rb->dhost = dcr_map(mpic->node, phys_addr + offset, size);
        BUG_ON(!DCR_MAP_OK(rb->dhost));
 }