[gtk+] Remove gtk4-install.props's during re-generation

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

commit 2e103e85cc61264faacb240c55baac149842c98f
Author: Chun-wei Fan <fanchunwei src gnome org>
Date:   Wed Oct 19 18:46:59 2016 +0800

    Remove gtk4-install.props's during re-generation
    
    This is to ensure the changes in the generated
    build/win32/vs10/gtk4-install.props are applied in
    build/win32/vs[11|12|14] as well.

 build/win32/vs10/Makefile.am |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)
---
diff --git a/build/win32/vs10/Makefile.am b/build/win32/vs10/Makefile.am
index 9b98666..de544a8 100644
--- a/build/win32/vs10/Makefile.am
+++ b/build/win32/vs10/Makefile.am
@@ -69,6 +69,9 @@ DISTCLEANFILES = \
        $(GENERATED_ITEMS)
 
 gtk4-install.props: $(top_srcdir)/build/win32/vs10/gtk4-install.propsin $(MSVC10_HEADERS_LISTS)
+       -$(RM) $(top_builddir)/build/win32/vs11/gtk4-install.props
+       -$(RM) $(top_builddir)/build/win32/vs12/gtk4-install.props
+       -$(RM) $(top_builddir)/build/win32/vs14/gtk4-install.props
        $(CPP) -P - <$(top_srcdir)/build/win32/vs10/gtk4-install.propsin >$@
        rm $(MSVC10_HEADERS_LISTS)