[gtkmm] Update .gitignore

[Kjell Ahlstedt <kjellahl src gnome org>]

commit d9851e3ede42c32ba6703ed6fb98b9fe583c0170
Author: Kjell Ahlstedt <kjellahlstedt gmail com>
Date:   Sat Sep 8 10:34:54 2018 +0200

    Update .gitignore

 .gitignore | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)
---
diff --git a/.gitignore b/.gitignore
index b73a3df1..261ae73f 100644
--- a/.gitignore
+++ b/.gitignore
@@ -25,10 +25,10 @@ stamp-h?
 /libtool
 
 # MSVC
-MSVC_Net201?/gdkmm/gdkmm.rc
-MSVC_Net201?/gdkmm/gdkmmconfig.h
-MSVC_Net201?/gtkmm/gtkmm.rc
-MSVC_Net201?/gtkmm/gtkmmconfig.h
+MSVC_NMake/gdkmm/gdkmm.rc
+MSVC_NMake/gdkmm/gdkmmconfig.h
+MSVC_NMake/gtkmm/gtkmm.rc
+MSVC_NMake/gtkmm/gtkmmconfig.h
 
 # demos
 demos/gtk-demo/demo_resources.c