libfdt: Remove no longer used code from fdt_node_offset_by_compatible()

Since fdt_node_offset_by_compatible() was converted to the new
fdt_next_node() iterator, a chunk of initialization code became
redundant, but was not removed by oversight.  This patch cleans it up.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

libfdt/fdt_ro.c

@@ -453,20 +453,10 @@ int fdt_node_check_compatible(const void *fdt, int nodeoffset,
 int fdt_node_offset_by_compatible(const void *fdt, int startoffset,
 				  const char *compatible)
 {
-	uint32_t tag;
-	int offset, nextoffset;
-	int err;
+	int offset, err;
 
 	CHECK_HEADER(fdt);
 
-	if (startoffset >= 0) {
-		tag = fdt_next_tag(fdt, startoffset, &nextoffset);
-		if (tag != FDT_BEGIN_NODE)
-			return -FDT_ERR_BADOFFSET;
-	} else {
-		nextoffset = 0;
-	}
-
 	/* FIXME: The algorithm here is pretty horrible: we scan each
 	 * property of a node in fdt_node_check_compatible(), then if
 	 * that didn't find what we want, we scan over them again