iwlwifi: use pci registers defined in pci_regs.h

This patch replaces where possible usage of pci register
defined in the driver by ones defined in pci_regs.h

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/iwlwifi/iwl-core.h b/drivers/net/wireless/iwlwifi/iwl-core.h
index d79912b..9d464ec 100644
--- a/drivers/net/wireless/iwlwifi/iwl-core.h
+++ b/drivers/net/wireless/iwlwifi/iwl-core.h
@@ -410,6 +410,14 @@
  *****************************************************/
 void iwl_disable_interrupts(struct iwl_priv *priv);
 void iwl_enable_interrupts(struct iwl_priv *priv);
+static inline u16 iwl_pcie_link_ctl(struct iwl_priv *priv)
+{
+	int pos;
+	u16 pci_lnk_ctl;
+	pos = pci_find_capability(priv->pci_dev, PCI_CAP_ID_EXP);
+	pci_read_config_word(priv->pci_dev, pos + PCI_EXP_LNKCTL, &pci_lnk_ctl);
+	return pci_lnk_ctl;
+}
 
 /*****************************************************
 *  Error Handling Debugging