As discussed with SG10, bump version of __cpp_deduction_guides macro to indicate support for P0620R0.

llvm-svn: 333587
diff --git a/clang/test/Lexer/cxx-features.cpp b/clang/test/Lexer/cxx-features.cpp
index 352f08e..a005851 100644
--- a/clang/test/Lexer/cxx-features.cpp
+++ b/clang/test/Lexer/cxx-features.cpp
@@ -57,7 +57,7 @@
 
 // static_assert checked below
 
-#if check(deduction_guides, 0, 0, 0, 201611)
+#if check(deduction_guides, 0, 0, 0, 201703)
 #error "wrong value for __cpp_deduction_guides"
 #endif