KVM: fix TASK_DELAY_ACCT kconfig warning

Fix kconfig dependency warning:

warning: (KVM) selects TASK_DELAY_ACCT which has unmet direct dependencies (TASKSTATS)

Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Avi Kivity <avi@redhat.com>
diff --git a/arch/x86/kvm/Kconfig b/arch/x86/kvm/Kconfig
index 988724b..0a09b58 100644
--- a/arch/x86/kvm/Kconfig
+++ b/arch/x86/kvm/Kconfig
@@ -31,6 +31,7 @@
 	select KVM_ASYNC_PF
 	select USER_RETURN_NOTIFIER
 	select KVM_MMIO
+	select TASKSTATS
 	select TASK_DELAY_ACCT
 	---help---
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