hw/i2c: Rename i2c_create_slave() as i2c_slave_create_simple()

We use "create_simple" names for functions that allocate, initialize,
configure and realize device objects: pci_create_simple(),
isa_create_simple(), usb_create_simple(). For consistency, rename
i2c_create_slave() as i2c_slave_create_simple(). Since we have
to update all the callers, also let it return a I2CSlave object.

Suggested-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Corey Minyard <cminyard@mvista.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20200705224154.16917-5-f4bug@amsat.org>
Signed-off-by: Corey Minyard <cminyard@mvista.com>
diff --git a/hw/arm/stellaris.c b/hw/arm/stellaris.c
index 7156fb3..28eb15c 100644
--- a/hw/arm/stellaris.c
+++ b/hw/arm/stellaris.c
@@ -1380,7 +1380,7 @@
                                    qdev_get_gpio_in(nvic, 8));
         i2c = (I2CBus *)qdev_get_child_bus(dev, "i2c");
         if (board->peripherals & BP_OLED_I2C) {
-            i2c_create_slave(i2c, "ssd0303", 0x3d);
+            i2c_slave_create_simple(i2c, "ssd0303", 0x3d);
         }
     }