[POWERPC] bootwrapper: Add ft_find_device_rel().

Add a function to look up a relative, rather than absolute, path name.
Signed-off-by: NScott Wood <scottwood@freescale.com>
Acked-by: NMark A. Greer <mgreer@mvista.com>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

arch/powerpc/boot/flatdevtree.c

@@ -654,6 +654,19 @@ void *ft_find_device(struct ft_cxt *cxt, const char *srch_path)
 	return ft_get_phandle(cxt, node);
 }
 
+void *ft_find_device_rel(struct ft_cxt *cxt, const void *top,
+                         const char *srch_path)
+{
+	char *node;
+
+	node = ft_node_ph2node(cxt, top);
+	if (node == NULL)
+		return NULL;
+
+	node = ft_find_descendent(cxt, node, srch_path);
+	return ft_get_phandle(cxt, node);
+}
+
 void *ft_find_descendent(struct ft_cxt *cxt, void *top, const char *srch_path)
 {
 	struct ft_atom atom;

arch/powerpc/boot/flatdevtree.h

@@ -97,6 +97,8 @@ int ft_add_rsvmap(struct ft_cxt *cxt, u64 physaddr, u64 size);
 void ft_dump_blob(const void *bphp);
 void ft_merge_blob(struct ft_cxt *cxt, void *blob);
 void *ft_find_device(struct ft_cxt *cxt, const char *srch_path);
+void *ft_find_device_rel(struct ft_cxt *cxt, const void *top,
+                         const char *srch_path);
 void *ft_find_descendent(struct ft_cxt *cxt, void *top, const char *srch_path);
 int ft_get_prop(struct ft_cxt *cxt, const void *phandle, const char *propname,
 		void *buf, const unsigned int buflen);