fdt: introduce fdt_verify_alias_address() and fdt_get_base_address()

Introduce two functions, fdt_verify_alias_address() and
fdt_get_base_address(), which can be used to verify the physical address
of a device in a device tree.

fdt_get_base_address() returns the base address of an SOC or PCI node.

fdt_verify_alias_address() prints a message if the address of a node
specified by an alias does not match the given physical address.

Signed-off-by: Timur Tabi <timur@freescale.com>
diff --git a/include/fdt_support.h b/include/fdt_support.h
index ce6817b..cefc990 100644
--- a/include/fdt_support.h
+++ b/include/fdt_support.h
@@ -90,5 +90,9 @@
 int fdt_alloc_phandle(void *blob);
 int fdt_add_edid(void *blob, const char *compat, unsigned char *buf);
 
+int fdt_verify_alias_address(void *fdt, int anode, const char *alias,
+			      u64 addr);
+u64 fdt_get_base_address(void *fdt, int node);
+
 #endif /* ifdef CONFIG_OF_LIBFDT */
 #endif /* ifndef __FDT_SUPPORT_H */