Fix version number generation from tarballs on openbsd

Thanks to fred for reporting this

version.sh

@@ -16,6 +16,8 @@ else
 	# Figure out the information we need
 	LATEST_TAG=`${GIT} describe --abbrev=0 HEAD`
 	COMMITS_SINCE=`${GIT} log --format=oneline ${LATEST_TAG}..HEAD | wc -l`
+	# Explicitly make it a number: on openbsd wc -l returns "    42" instead of "42"
+	let COMMITS_SINCE=COMMITS_SINCE
 	SHORT_ID=`${GIT} rev-parse --short HEAD`
 
 	if [ "x$COMMITS_SINCE" = "x0" ]