bus/pci: remove unused x86 Linux constant

[ upstream commit b62f3af ]

This macro is unused after a previous fix.

Fixes: fe822eb ("bus/pci: use IOVA DMA mask check when setting IOVA mode")

Signed-off-by: David Marchand <david.marchand@redhat.com>

drivers/bus/pci/linux/pci.c

@@ -583,7 +583,6 @@ pci_one_device_iommu_support_va(struct rte_pci_device *dev)
 {
 #define VTD_CAP_MGAW_SHIFT	16
 #define VTD_CAP_MGAW_MASK	(0x3fULL << VTD_CAP_MGAW_SHIFT)
-#define X86_VA_WIDTH 47 /* From Documentation/x86/x86_64/mm.txt */
 	struct rte_pci_addr *addr = &dev->addr;
 	char filename[PATH_MAX];
 	FILE *fp;