powerpc: Remove legacy iSeries from ppc64_defconfig

Since we are heading towards removing the Legacy iSeries platform, start
by no longer building it for ppc64_defconfig.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

arch/powerpc/configs/ppc64_defconfig

@@ -24,10 +24,6 @@ CONFIG_PPC_SPLPAR=y
 CONFIG_SCANLOG=m
 CONFIG_PPC_SMLPAR=y
 CONFIG_DTL=y
-CONFIG_PPC_ISERIES=y
-CONFIG_VIODASD=y
-CONFIG_VIOCD=m
-CONFIG_VIOTAPE=m
 CONFIG_PPC_MAPLE=y
 CONFIG_PPC_PASEMI=y
 CONFIG_PPC_PASEMI_IOMMU=y
@@ -259,7 +255,6 @@ CONFIG_PASEMI_MAC=y
 CONFIG_MLX4_EN=m
 CONFIG_QLGE=m
 CONFIG_BE2NET=m
-CONFIG_ISERIES_VETH=m
 CONFIG_PPP=m
 CONFIG_PPP_ASYNC=m
 CONFIG_PPP_SYNC_TTY=m