lib.sh: always sanitize xbmkver before writing

this removed the need to check it in xbmk_set_version
as it calls update_xbmkver, which in turn performs
the same check.

this increases the general reliability and safety of
xbmk when recording its own version after update.

Signed-off-by: Leah Rowe <leah@libreboot.org>

include/init.sh

@@ -259,10 +259,6 @@ xbmk_set_version()
 		versiondate="$(git show --no-patch --no-notes \
 		    --pretty='%ct' HEAD)" || versiondate="$versiondate_"
 
-	if [ -z "$version" ] || [ -z "$versiondate" ]; then
-		err "version and/or versiondate unset" "xbmk_set_version" "$@"
-	fi
-
 	update_xbmkver "."
 
 	relname="$projectname-$version"