[libsoup] README.msvc: Inform to disable tests on older MSVC

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

commit ee58ada474828318472f5620940f1516efe80024
Author: Chun-wei Fan <fanchunwei src gnome org>
Date:   Wed Aug 26 16:34:55 2020 +0800

    README.msvc: Inform to disable tests on older MSVC
    
    The test programs have been written in C99, which will not work on older
    Visual Studio (pre-2013), so let people know that they may want to build
    without the tests in this situation.

 README.msvc | 2 ++
 1 file changed, 2 insertions(+)
---
diff --git a/README.msvc b/README.msvc
index 5855c487..86447e0b 100644
--- a/README.msvc
+++ b/README.msvc
@@ -55,6 +55,8 @@ To do a build using Meson, do the following:
     python $(PYTHON_INSTALL_DIR)\scripts\meson.py $(LIBSOUP_SRCDIR) --buildtype=$(build_configuration) 
--prefix=$(INSTALL_PREFIX) -Dsysprof=disabled [--backend=vs]
 
  Also pass in -Dgssapi=false if not building with GSSAPI support.
+ For pre-Visual Studio 2013, pass in -Dtests=false, since the tests are written in
+ C99 syntax.
 
  Please see the Meson docs for an explanation for --buildtype, the path passed for
  --prefix need not to be on the same drive as where the build is carried out, but