PCI: designware: Add dw_pcie prefix before cfg_read/write

The cfg_read/write functions are DesignWare-specific.  Add dw_pcie prefix
to avoid collision in global name space.

Tested-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Pratyush Anand <pratyush.anand@st.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Jagannadha Sutradharudu Teki <jagannadh.teki@gmail.com>
Acked-by: Jingoo Han <jg1.han@samsung.com>
diff --git a/drivers/pci/host/pcie-designware.h b/drivers/pci/host/pcie-designware.h
index c15379b..3063b35 100644
--- a/drivers/pci/host/pcie-designware.h
+++ b/drivers/pci/host/pcie-designware.h
@@ -66,8 +66,8 @@
 	void (*host_init)(struct pcie_port *pp);
 };
 
-int cfg_read(void __iomem *addr, int where, int size, u32 *val);
-int cfg_write(void __iomem *addr, int where, int size, u32 val);
+int dw_pcie_cfg_read(void __iomem *addr, int where, int size, u32 *val);
+int dw_pcie_cfg_write(void __iomem *addr, int where, int size, u32 val);
 void dw_handle_msi_irq(struct pcie_port *pp);
 void dw_pcie_msi_init(struct pcie_port *pp);
 int dw_pcie_link_up(struct pcie_port *pp);