KVM: Use cond_resched() directly and remove useless kvm_resched()

Since the commit 15ad7146 ("KVM: Use the scheduler preemption notifiers
to make kvm preemptible"), the remaining stuff in this function is a
simple cond_resched() call with an extra need_resched() check which was
there to avoid dropping VCPUs unnecessarily.  Now it is meaningless.

Signed-off-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

virt/kvm/kvm_main.c

@@ -1710,14 +1710,6 @@ void kvm_vcpu_kick(struct kvm_vcpu *vcpu)
 EXPORT_SYMBOL_GPL(kvm_vcpu_kick);
 #endif /* !CONFIG_S390 */
 
-void kvm_resched(struct kvm_vcpu *vcpu)
-{
-	if (!need_resched())
-		return;
-	cond_resched();
-}
-EXPORT_SYMBOL_GPL(kvm_resched);
-
 bool kvm_vcpu_yield_to(struct kvm_vcpu *target)
 {
 	struct pid *pid;