dm: core: Drop unused parameter from dm_extended_scan_fdt()

This doesn't need to be passed the devicetree anymore. Drop it.
Also rename the function to drop the _fdt suffix.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/test/dm/test-fdt.c b/test/dm/test-fdt.c
index 9507636..673ffb4 100644
--- a/test/dm/test-fdt.c
+++ b/test/dm/test-fdt.c
@@ -257,7 +257,7 @@
 	int ret;
 	int i;
 
-	ret = dm_extended_scan_fdt(gd->fdt_blob, false);
+	ret = dm_extended_scan(false);
 	ut_assert(!ret);
 
 	ret = uclass_get(UCLASS_TEST_FDT, &uc);