patch 8.2.0246: MSVC: deprecation warnings with Ruby

Problem:    MSVC: deprecation warnings with Ruby.
Solution:   Move _CRT_SECURE_NO_DEPRECATE to build file. (Ken Takata,
            closes #5622)
diff --git a/src/Make_mvc.mak b/src/Make_mvc.mak
index c51f804..5097081 100644
--- a/src/Make_mvc.mak
+++ b/src/Make_mvc.mak
@@ -657,6 +657,8 @@
 !  if "$(OPTIMIZE)" != "SPACE"
 OPTFLAG = $(OPTFLAG) /GL
 !  endif
+# Visual Studio 2005 has 'deprecated' many of the standard CRT functions
+CFLAGS = $(CFLAGS) /D_CRT_SECURE_NO_DEPRECATE /D_CRT_NONSTDC_NO_DEPRECATE
 ! endif
 
 # (/Wp64 is deprecated in VC9 and generates an obnoxious warning.)