fdt: Export fdtdec_lookup() and fix the name

The name of this function is not consistent, so fix it, and export
the function for external use.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/include/fdtdec.h b/include/fdtdec.h
index e70714b..f8a4e94 100644
--- a/include/fdtdec.h
+++ b/include/fdtdec.h
@@ -110,6 +110,19 @@
 		enum fdt_compat_id id, int *upto);
 
 /**
+ * Find the compatible ID for a given node.
+ *
+ * Generally each node has at least one compatible string attached to it.
+ * This function looks through our list of known compatible strings and
+ * returns the corresponding ID which matches the compatible string.
+ *
+ * @param blob		FDT blob to use
+ * @param node		Node containing compatible string to find
+ * @return compatible ID, or COMPAT_UNKNOWN if we cannot find a match
+ */
+enum fdt_compat_id fdtdec_lookup(const void *blob, int node);
+
+/**
  * Find the next compatible node for a peripheral.
  *
  * Do the first call with node = 0. This function will return a pointer to
diff --git a/lib/fdtdec.c b/lib/fdtdec.c
index 32f03cc..96f3e7b 100644
--- a/lib/fdtdec.c
+++ b/lib/fdtdec.c
@@ -128,7 +128,7 @@
 	return 1;
 }
 
-enum fdt_compat_id fd_dec_lookup(const void *blob, int node)
+enum fdt_compat_id fdtdec_lookup(const void *blob, int node)
 {
 	enum fdt_compat_id id;