hw/ppc/40p: Move the MC146818 RTC to the board where it belongs

The MC146818 RTC was incorrectly added to the i82378 chipset in
commit a04ff94097. In the next commit (506b7ddf88) the PReP
machine use the i82378.
Since the MC146818 is specific to the PReP machine, move its use
there.

Fixes: a04ff94097
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20190505152839.18650-3-philmd@redhat.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

hw/isa/i82378.c

@@ -21,7 +21,6 @@
 #include "hw/pci/pci.h"
 #include "hw/i386/pc.h"
 #include "hw/timer/i8254.h"
-#include "hw/timer/mc146818rtc.h"
 #include "hw/audio/pcspk.h"
 
 #define TYPE_I82378 "i82378"
@@ -105,9 +104,6 @@ static void i82378_realize(PCIDevice *pci, Error **errp)
 
     /* 2 82C37 (dma) */
     isa = isa_create_simple(isabus, "i82374");
-
-    /* timer */
-    isa_create_simple(isabus, TYPE_MC146818_RTC);
 }
 
 static void i82378_init(Object *obj)

hw/ppc/prep.c

@@ -675,6 +675,9 @@ static void ibm_40p_init(MachineState *machine)
     qdev_prop_set_uint32(dev, "ram-size", machine->ram_size);
     qdev_init_nofail(dev);
 
+    /* RTC */
+    isa_create_simple(isa_bus, TYPE_MC146818_RTC);
+
     /* initialize CMOS checksums */
     cmos_checksum = 0x6aa9;
     qbus_walk_children(BUS(isa_bus), prep_set_cmos_checksum, NULL, NULL, NULL,