KVM: ia64: Define printk function for kvm-intel module

kvm-intel module is relocated to an isolated address space
with kernel, so it can't call host kernel's printk for debug
purpose. In the module, we implement the printk to output debug
info of vmm.

Signed-off-by: Xiantao Zhang <xiantao.zhang@intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>