hv:enable GVT-d for pre-launched linux guest in logical partion mode

When pass-thru GPU to pre-launched Linux guest,
need to pass GPU OpRegion to the guest.
Here's the detailed steps:
1. reserve a memory region in ve820 table for GPU OpRegion
2. build EPT mapping for GPU OpRegion to pass-thru OpRegion to guest
3. emulate the pci config register for OpRegion
For the third step, here's detailed description:
The address of OpRegion locates on PCI config space offset 0xFC,
Normal Linux guest won't write this register,
so we can regard this register as read-only.
When guest reads this register, return the emulated value.
When guest writes this register, ignore the operation.

Tracked-On: #6387

Signed-off-by: Liu,Junming <junming.liu@intel.com>

hypervisor/include/common/ptdev.h

@@ -19,6 +19,11 @@ enum intx_ctlr {
 #define PTDEV_INTR_MSI		(1U << 0U)
 #define PTDEV_INTR_INTX		(1U << 1U)
 
+#define GPU_OPREGION_SIZE	0x5000U
+#define GPU_OPREGION_GPA	0x40880000U
+#define PCIR_ASLS_CTL		0xfcU /* register offset in PCIe configuration space for Opregion base address */
+#define PCIM_ASLS_OPREGION_MASK	0xfffff000U /* opregion need 4KB aligned */
+
 #define INVALID_PTDEV_ENTRY_ID 0xffffU
 
 #define DEFINE_MSI_SID(name, a, b)	\