fixup! msvc: add a Makefile target to pre-generate the VS solution

The Perl project is now built without using MakeMaker, and therefore the
way we need to build vcxproj changed, too.

Signed-off-by: Johannes Schindelin <[email protected]>

Author: dscho

config.mak.uname

@@ -746,8 +746,8 @@ vcxproj:
 	git add -f $(SCRIPT_LIB) $(SCRIPT_SH_GEN) $(SCRIPT_PERL_GEN)
 
 	# Add Perl module
-	$(MAKE) -C perl
-	git add -f perl/blib/lib
+	$(MAKE) $(LIB_PERL_GEN)
+	git add -f perl/build
 
 	# Add bin-wrappers, for testing
 	rm -rf bin-wrappers/