man: devlink-region: fix typo in example

devlink-region does not accept the legth param, but the length one.

Fixes: 8b4fbf0bed8e ("devlink: Add support for devlink-region access")
Signed-off-by: Andrea Claudi <aclaudi@redhat.com>
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
1 file changed