patch 8.0.1474: Visual C 2017 has multiple MSVCVER numbers

Problem:    Visual C 2017 has multiple MSVCVER numbers.
Solution:   Assume the 2017 version if MSVCVER >= 1910. (Leonardo Valeri
            Manera, closes #2619)
diff --git a/src/Make_mvc.mak b/src/Make_mvc.mak
index c2e808c..65da331 100644
--- a/src/Make_mvc.mak
+++ b/src/Make_mvc.mak
@@ -289,7 +289,8 @@
 MSVCRT_VER = ($(MSVCVER) / 10 - 60)
 # Visual C++ 2017 needs special handling
 # it has an _MSC_VER of 1910->14.1, but is actually v15 with runtime v140
-!elseif $(MSVCVER) == 1910
+# TODO: what's the maximum value?
+!elseif $(MSVCVER) >= 1910
 MSVC_MAJOR = 15
 MSVCRT_VER = 140
 !else