[gtk/gtk-3-24] win32/Makefile-newvs.am: Fix 'make dist'

[Chun-wei Fan <fanchunwei src gnome org>]

commit 8f325b475b7d2dcd49d311c9c2aba87d06b05a15
Author: Chun-wei Fan <fanchunwei src gnome org>
Date:   Thu Dec 24 17:05:10 2020 +0800

    win32/Makefile-newvs.am: Fix 'make dist'
    
    We need to account for the lack of Directory.Build.props in win32/vs10...

 win32/Makefile-newvs.am | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)
---
diff --git a/win32/Makefile-newvs.am b/win32/Makefile-newvs.am
index e5c7581288..9cda120c7a 100644
--- a/win32/Makefile-newvs.am
+++ b/win32/Makefile-newvs.am
@@ -41,8 +41,10 @@ endif
 %.props: $(top_builddir)/win32/vs10/Makefile
        if test -e $(top_srcdir)/win32/vs10/$@; then \
                sed 's/<VSVer>10<\/VSVer>/<VSVer>$(MSVC_VER)<\/VSVer>/g' < $(top_srcdir)/win32/vs10/$@ > 
$(top_builddir)/win32/vs$(MSVC_VER)/$@; \
-       else \
+       elif test -e $(top_builddir)/win32/vs10/$@; then \
                sed 's/<VSVer>10<\/VSVer>/<VSVer>$(MSVC_VER)<\/VSVer>/g' < $(top_builddir)/win32/vs10/$@ > 
$(top_builddir)/win32/vs$(MSVC_VER)/$@; \
+       else \
+               : \
        fi
 
 %.vcxproj.filters: $(top_builddir)/win32/vs10/Makefile