of/pci: Add of_pci_dma_range_parser_init() for dma-ranges parsing support

Several host bridge drivers duplicate of_pci_range_parser_init() in order
to parse their dma-ranges property.

Provide of_pci_dma_range_parser_init() for that use case.

Signed-off-by: Marc Gonzalez <marc_gonzalez@sigmadesigns.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/include/linux/of_address.h b/include/linux/of_address.h
index 3786473..8beed2d 100644
--- a/include/linux/of_address.h
+++ b/include/linux/of_address.h
@@ -49,6 +49,8 @@ extern const __be32 *of_get_address(struct device_node *dev, int index,
 
 extern int of_pci_range_parser_init(struct of_pci_range_parser *parser,
 			struct device_node *node);
+extern int of_pci_dma_range_parser_init(struct of_pci_range_parser *parser,
+			struct device_node *node);
 extern struct of_pci_range *of_pci_range_parser_one(
 					struct of_pci_range_parser *parser,
 					struct of_pci_range *range);
@@ -85,7 +87,13 @@ static inline const __be32 *of_get_address(struct device_node *dev, int index,
 static inline int of_pci_range_parser_init(struct of_pci_range_parser *parser,
 			struct device_node *node)
 {
-	return -1;
+	return -ENOSYS;
+}
+
+static inline int of_pci_dma_range_parser_init(struct of_pci_range_parser *parser,
+			struct device_node *node)
+{
+	return -ENOSYS;
 }
 
 static inline struct of_pci_range *of_pci_range_parser_one(