freedreno: add default .dir-locals.el for emacs settings

Signed-off-by: Ilia Mirkin <imirkin@alum.mit.edu>

src/gallium/drivers/freedreno/.dir-locals.el

@@ -0,0 +1,8 @@
+((nil
+  (indent-tabs-mode . true)
+  (tab-width . 4)
+  (c-basic-offset . 4)
+  (c-file-style . "k&r")
+  (fill-column . 78)
+  )
+ )