x86/vmx: replace CONFIG_HVM with CONFIG_INTEL_VMX in vmx.h

As now we got a separate config option for VMX which itself depends on
CONFIG_HVM, we need to use it to provide vmx_pi_hooks_{assign,deassign}
stubs for case when VMX is disabled while HVM is enabled.

Signed-off-by: Sergiy Kibrik <Sergiy_Kibrik@epam.com>
Acked-by: Jan Beulich <jbeulich@suse.com>

xen/arch/x86/include/asm/hvm/vmx/vmx.h

@@ -599,7 +599,7 @@ void vmx_pi_desc_fixup(unsigned int cpu);
 
 void vmx_sync_exit_bitmap(struct vcpu *v);
 
-#ifdef CONFIG_HVM
+#ifdef CONFIG_INTEL_VMX
 void vmx_pi_hooks_assign(struct domain *d);
 void vmx_pi_hooks_deassign(struct domain *d);
 #else