KVM: VMX: Initialize vmx->guest_msrs[] right after allocation

Move the initialization of vmx->guest_msrs[] from vmx_vcpu_setup() to
vmx_create_vcpu(), and put it right after its allocation.

This also is the preperation for next patch.

Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>