[gtk-doc] build: update gitignore

[Stefan Sauer <stefkost src gnome org>]

commit 3c063041fdf2b1ecfe8800629196942a34ea2935
Author: Stefan Sauer <ensonic users sf net>
Date:   Wed Mar 29 23:24:48 2017 +0200

    build: update gitignore

 Makefile.am |    4 +++-
 1 files changed, 3 insertions(+), 1 deletions(-)
---
diff --git a/Makefile.am b/Makefile.am
index 9998d44..f1c1e9f 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -64,10 +64,12 @@ EXTRA_DIST = \
 
 CLEANFILES = \
   gtk-doc.flat.make \
+  gtkdoc-checkc \
   gtkdoc-depscanc \
   gtkdoc-mkhtmlc \
   gtkdoc-mkmanc \
-  gtkdoc-mkpdfc
+  gtkdoc-mkpdfc \
+  gtkdoc-rebasec
 
 DISTCLEANFILES = \
   gtkdoc-check \