PCI: Add PCI_EXP_LNKCTL2_TLS* macros

The Link Control 2 register is missing macros for Target Link Speeds.  Add
those in.

Signed-off-by: Frederick Lawler <fred@fredlawl.com>
[bhelgaas: use "GT" instead of "GB"]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

include/uapi/linux/pci_regs.h

@@ -655,6 +655,11 @@
 #define  PCI_EXP_LNKCAP2_SLS_16_0GB	0x00000010 /* Supported Speed 16GT/s */
 #define  PCI_EXP_LNKCAP2_CROSSLINK	0x00000100 /* Crosslink supported */
 #define PCI_EXP_LNKCTL2		48	/* Link Control 2 */
+#define PCI_EXP_LNKCTL2_TLS		0x000f
+#define PCI_EXP_LNKCTL2_TLS_2_5GT	0x0001 /* Supported Speed 2.5GT/s */
+#define PCI_EXP_LNKCTL2_TLS_5_0GT	0x0002 /* Supported Speed 5GT/s */
+#define PCI_EXP_LNKCTL2_TLS_8_0GT	0x0003 /* Supported Speed 8GT/s */
+#define PCI_EXP_LNKCTL2_TLS_16_0GT	0x0004 /* Supported Speed 16GT/s */
 #define PCI_EXP_LNKSTA2		50	/* Link Status 2 */
 #define PCI_CAP_EXP_ENDPOINT_SIZEOF_V2	52	/* v2 endpoints with link end here */
 #define PCI_EXP_SLTCAP2		52	/* Slot Capabilities 2 */