add gitignores for Blackfin pieces

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
diff --git a/board/bf533-ezkit/.gitignore b/board/bf533-ezkit/.gitignore
new file mode 100644
index 0000000..945f324
--- /dev/null
+++ b/board/bf533-ezkit/.gitignore
@@ -0,0 +1 @@
+/u-boot.lds