powerpc: Enable KSM on pseries and ppc64 defconfigs

KSM will only be used on areas marked for merging via madvise, and it
is showing nice improvements on KVM workloads, so enable it by
default.
Signed-off-by: NAnton Blanchard <anton@samba.org>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

arch/powerpc/configs/ppc64_defconfig

@@ -49,6 +49,7 @@ CONFIG_KEXEC=y
 CONFIG_CRASH_DUMP=y
 CONFIG_IRQ_ALL_CPUS=y
 CONFIG_MEMORY_HOTREMOVE=y
+CONFIG_KSM=y
 CONFIG_SCHED_SMT=y
 CONFIG_PCCARD=y
 CONFIG_ELECTRA_CF=y

arch/powerpc/configs/pseries_defconfig

@@ -46,6 +46,7 @@ CONFIG_KEXEC=y
 CONFIG_IRQ_ALL_CPUS=y
 CONFIG_MEMORY_HOTPLUG=y
 CONFIG_MEMORY_HOTREMOVE=y
+CONFIG_KSM=y
 CONFIG_TRANSPARENT_HUGEPAGE=y
 CONFIG_PPC_64K_PAGES=y
 CONFIG_PPC_SUBPAGE_PROT=y

arch/powerpc/configs/pseries_le_defconfig

@@ -47,6 +47,7 @@ CONFIG_KEXEC=y
 CONFIG_IRQ_ALL_CPUS=y
 CONFIG_MEMORY_HOTPLUG=y
 CONFIG_MEMORY_HOTREMOVE=y
+CONFIG_KSM=y
 CONFIG_TRANSPARENT_HUGEPAGE=y
 CONFIG_PPC_64K_PAGES=y
 CONFIG_PPC_SUBPAGE_PROT=y