.gitignore: Ignore new autofoo tmp files

Change-Id: Iaf853783679815e74b6b8e5f3e8631c53ed20613
diff --git a/.gitignore b/.gitignore
index ede9b4e..738b3c4 100644
--- a/.gitignore
+++ b/.gitignore
@@ -6,6 +6,7 @@
 .deps
 .libs
 .dirstamp
+*~
 
 # Generated by autoconf/configure
 Makefile