build: notify about the redundancy of "nosign"

vcbuild doesn't sign by default since
92ed1ab, but there might be people who
haven't noticed the change. This adds a message informing them that
"nosign" is no longer necessary.

PR-URL: nodejs#11119
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Sakthipriyan Vairamani <thechargingvolcano@gmail.com>

vcbuild.bat

@@ -51,7 +51,7 @@ if /i "%1"=="x64"           set target_arch=x64&goto arg-ok
 if /i "%1"=="vc2015"        set target_env=vc2015&goto arg-ok
 if /i "%1"=="noprojgen"     set noprojgen=1&goto arg-ok
 if /i "%1"=="nobuild"       set nobuild=1&goto arg-ok
-if /i "%1"=="nosign"        set "sign="&goto arg-ok
+if /i "%1"=="nosign"        set "sign="&echo Note: vcbuild no longer signs by default. "nosign" is redundant.&goto arg-ok
 if /i "%1"=="sign"          set sign=1&goto arg-ok
 if /i "%1"=="nosnapshot"    set nosnapshot=1&goto arg-ok
 if /i "%1"=="noetw"         set noetw=1&goto arg-ok