Fixup: Update the value of __cpp_lib_chrono in table "Standard library feature-test macros".

Author: Dawn Perchik

source/support.tex

@@ -561,7 +561,7 @@
   \tcode{<atomic>} \tcode{<filesystem>} \tcode{<istream>} \tcode{<limits>}
   \tcode{<locale>} \tcode{<ostream>} \tcode{<string>} \tcode{<string_view>}
   \\ \rowsep
-\defnlibxname{cpp_lib_chrono}                               & \tcode{201611L} &
+\defnlibxname{cpp_lib_chrono}                               & \tcode{201907L} &
   \tcode{<chrono>} \\ \rowsep
 \defnlibxname{cpp_lib_chrono_udls}                          & \tcode{201304L} &
   \tcode{<chrono>} \\ \rowsep