After commit ad67b74d ("printk: hash addresses printed with %p"),
it will print "____ptrval____" instead of actual addresses when mbigen
create domain fails,

  Hisilicon MBIGEN-V2 HISI0152:00: Failed to create mbi-gen@(____ptrval____) irqdomain
  Hisilicon MBIGEN-V2: probe of HISI0152:00 failed with error -12

dev_xxx() helper contains the device info, HISI0152:00, which stands for
mbigen ACPI HID and its UID, we can identify the failing probed mbigen,
so just remove the printing "mgn_chip->base", and also add missing "\n".
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Reviewed-by: Hanjun Guo <guohanjun@huawei.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>