version: add Windows MAJOR,MINOR,BUILD,REVISON value

Updates #778

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>

version/version.h.do

@@ -5,7 +5,13 @@ read -r short <short.txt
 # get it into "major.minor.patch" format
 ver=$(echo "$ver" | sed -e 's/-/./')
 
+# winres is the MAJOR,MINOR,BUILD,REVISION 4-tuple used to identify
+# the version of Windows binaries. We always set REVISION to 0, which
+# seems to be how you map SemVer.
+winres=$(echo "$short,0" | sed -e 's/\./,/g')
+
 (
 	printf '#define TAILSCALE_VERSION_LONG "%s"\n' "$long"
 	printf '#define TAILSCALE_VERSION_SHORT "%s"\n' "$short"
+	printf '#define TAILSCALE_VERSION_WIN_RES %s\n' "$winres"
 ) >$3