sysbus devices should use the associated helper function instead of
calling memory_region_add_subregion() manually. This simplifies
slightly the code.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Aleksandar Markovic <amarkovic@wavecomp.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
---
 hw/mips/mips_mipssim.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/hw/mips/mips_mipssim.c b/hw/mips/mips_mipssim.c
index 3cd0e6eb33..2c2c7f25b2 100644
--- a/hw/mips/mips_mipssim.c
+++ b/hw/mips/mips_mipssim.c
@@ -227,8 +227,7 @@ mips_mipssim_init(MachineState *machine)
         qdev_set_legacy_instance_id(dev, 0x3f8, 2);
         qdev_init_nofail(dev);
         sysbus_connect_irq(SYS_BUS_DEVICE(dev), 0, env->irq[4]);
-        memory_region_add_subregion(get_system_io(), 0x3f8,
-                                    &SERIAL_IO(dev)->serial.io);
+        sysbus_add_io(SYS_BUS_DEVICE(dev), 0x3f8, &SERIAL_IO(dev)->serial.io);
     }
 
     if (nd_table[0].used)
-- 
2.24.0.308.g228f53135a