VMX: don't allow PVH to reach handle_mmio()

PVH guests accessing I/O ports via string ops is not supported yet.

Reported-by: Roger Pau Monné <roger.pau@citrix.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Mukesh Rathor <mukesh.rathor@oracle.com>
Acked-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Kevin Tian <kevin.tian@intel.com>
Release-Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>

xen/arch/x86/hvm/vmx/vmx.c

@@ -3086,7 +3086,8 @@ void vmx_vmexit_handler(struct cpu_user_regs *regs)
         if ( exit_qualification & 0x10 )
         {
             /* INS, OUTS */
-            if ( !handle_mmio() )
+            if ( unlikely(is_pvh_vcpu(v)) /* PVH fixme */ ||
+                 !handle_mmio() )
                 hvm_inject_hw_exception(TRAP_gp_fault, 0);
         }
         else