powerpc: add SATA_MV to ppc64_defconfig

This makes ppc64_defconfig bootable without initrd on pasemi systems,
most of whom have MV SATA controllers. Some have SIL24, but that driver
is already enabled.
Signed-off-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

arch/powerpc/configs/ppc64_defconfig

@@ -186,6 +186,7 @@ CONFIG_SCSI_DH_RDAC=m
 CONFIG_SCSI_DH_ALUA=m
 CONFIG_ATA=y
 CONFIG_SATA_SIL24=y
+CONFIG_SATA_MV=y
 CONFIG_SATA_SVW=y
 CONFIG_MD=y
 CONFIG_BLK_DEV_MD=y