VS: Map the link `/debug` flag for v142

Apply the changes from commit a5d9aa50 (VS: Map the link `/debug` to
its IDE property, 2018-11-21) and commit f77320c1 (VS: Add v140 and
v141 flag table entries for /DEBUG:NONE and /DEBUG:FULL, 2018-11-21) to
the v142 flag table.

See commit ae44496e (VS: Fix GenerateDebugInformation values for v140
and v141 toolsets, 2017-06-27, v3.9.0-rc6~15^2~1) for explanation.