fix documentation error: volume-opt in service create
@@ -426,7 +426,7 @@ The following options can only be used for named volumes (`type=volume`);
Options specific to a given volume driver, which will be passed to the
driver when creating the volume. Options are provided as a comma-separated
list of key/value pairs, for example,
- <tt>volume-opt=some-option=some-value,some-other-option=some-other-value</tt>.
+ <tt>volume-opt=some-option=some-value,volume-opt=some-other-option=some-other-value</tt>.
For available options for a given driver, refer to that driver's
documentation.
</td>
