x86/kvm: Fix pr_info() for async PF setup/teardown

'pr_fmt' already has 'kvm-guest: ' so 'KVM' prefix is redundant.
"Unregister pv shared memory" is very ambiguous, it's hard to
say which particular PV feature it relates to.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20210414123544.1060604-2-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

arch/x86/kernel/kvm.c

@@ -345,7 +345,7 @@ static void kvm_guest_cpu_init(void)
 
 		wrmsrl(MSR_KVM_ASYNC_PF_EN, pa);
 		__this_cpu_write(apf_reason.enabled, 1);
-		pr_info("KVM setup async PF for cpu %d\n", smp_processor_id());
+		pr_info("setup async PF for cpu %d\n", smp_processor_id());
 	}
 
 	if (kvm_para_has_feature(KVM_FEATURE_PV_EOI)) {
@@ -371,7 +371,7 @@ static void kvm_pv_disable_apf(void)
 	wrmsrl(MSR_KVM_ASYNC_PF_EN, 0);
 	__this_cpu_write(apf_reason.enabled, 0);
 
-	pr_info("Unregister pv shared memory for cpu %d\n", smp_processor_id());
+	pr_info("disable async PF for cpu %d\n", smp_processor_id());
 }
 
 static void kvm_pv_guest_cpu_reboot(void *unused)