PCI: pci-bridge-emul: Add PCIe Root Capabilities Register

The 16-bit Root Capabilities register is at offset 0x1e in the PCIe
Capability. Rename current 'rsvd' struct member to 'rootcap'.

Link: https://lore.kernel.org/r/20210722144041.12661-4-pali@kernel.org
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Marek Behún <kabel@kernel.org>

drivers/pci/pci-bridge-emul.h

@@ -54,7 +54,7 @@ struct pci_bridge_emul_pcie_conf {
 	__le16 slotctl;
 	__le16 slotsta;
 	__le16 rootctl;
-	__le16 rsvd;
+	__le16 rootcap;
 	__le32 rootsta;
 	__le32 devcap2;
 	__le16 devctl2;