Update .gitignore for files that should not be tracked.
diff --git a/.gitignore b/.gitignore
index 9ab93c0..3e34516 100644
--- a/.gitignore
+++ b/.gitignore
@@ -31,3 +31,13 @@ mingw32-config.cache
ext_deps
config.h.in
config.h
+
+ccan/libccan.a
+lib/arg-nonnull.h
+lib/c++defs.h
+lib/libgnu.a
+lib/signal.h
+lib/string.h
+lib/warn-on-use.h
+
+mkinstalldirs