.gitignore: Ignore new autofoo tmp files

Change-Id: I20b03d40214fe1822aab8df01e3c79404a795f01
diff --git a/.gitignore b/.gitignore
index 546d5df..466a744 100644
--- a/.gitignore
+++ b/.gitignore
@@ -14,6 +14,7 @@
 *.pyc
 *.gcda
 *.gcno
+*~
 
 #configure
 aclocal.m4