KVM: arm/arm64: Count guest exit due to various reasons

It would add guest exit statistics to debugfs, this can be helpful
while measuring KVM performance.

  [ Renamed some of the field names - Christoffer ]

Signed-off-by: Amit Singh Tomar <amittomer25@gmail.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>

arch/arm/kvm/mmio.c

@@ -210,8 +210,11 @@ int io_mem_abort(struct kvm_vcpu *vcpu, struct kvm_run *run,
 
 	if (!ret) {
 		/* We handled the access successfully in the kernel. */
+		vcpu->stat.mmio_exit_kernel++;
 		kvm_handle_mmio_return(vcpu, run);
 		return 1;
+	} else {
+		vcpu->stat.mmio_exit_user++;
 	}
 
 	run->exit_reason	= KVM_EXIT_MMIO;