[libsecret] Make 'distcheck' ignore files generated by code coverage

[Stefan Walter <stefw src gnome org>]

commit a0c5f206e57d56cf739e2fa9d4652cc6d0504fed
Author: Stef Walter <stefw gnome org>
Date:   Fri Jan 25 19:06:25 2013 +0100

    Make 'distcheck' ignore files generated by code coverage

 Makefile.am |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)
---
diff --git a/Makefile.am b/Makefile.am
index 6e4ef57..f5d56e9 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -52,3 +52,6 @@ dist-check-valac:
 endif
 
 dist-hook: dist-check-valac
+
+distcleancheck_listfiles =  \
+       find . -name '*.gc[dn][oa]' -prune -o -type f -print