KVM: Use pr_info/pr_err in kvm_main.c

KVM: Use pr_info/pr_err in kvm_main.c

WARNING: Prefer [subsystem eg: netdev]_info([subsystem]dev, ... then
dev_info(dev, ... then pr_info(...  to printk(KERN_INFO ...
+   printk(KERN_INFO "kvm: exiting hardware virtualization\n");

WARNING: Prefer [subsystem eg: netdev]_err([subsystem]dev, ... then
dev_err(dev, ... then pr_err(...  to printk(KERN_ERR ...
+	printk(KERN_ERR "kvm: misc device register failed\n");

Signed-off-by: Xiubo Li <lixiubo@cmss.chinamobile.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>