Ignore errors in dh_auto_clean

clean and distclean targets haven't been implemented, ignore.

Change-Id: I95e238aeaa023b8539ac0e2e43895dc944b22c14
diff --git a/debian/rules b/debian/rules
index e199f53..3eee9a0 100755
--- a/debian/rules
+++ b/debian/rules
@@ -3,6 +3,9 @@
 %:
 	dh $@
 
+override_dh_auto_clean:
+	-dh_auto_clean
+
 override_dh_auto_configure:
 	dh_auto_configure -- --disable-static --disable-x11 --disable-v4l2_core --disable-v4lsink PLATFORM=MX8