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>

arch/x86/kvm/Kconfig

@@ -31,6 +31,7 @@ config KVM
 	select KVM_ASYNC_PF
 	select USER_RETURN_NOTIFIER
 	select KVM_MMIO
+	select TASKSTATS
 	select TASK_DELAY_ACCT
 	---help---
 	  Support hosting fully virtualized guest machines using hardware