man: devlink-resource: add missing words in the example

man: devlink-resource: add missing words in the example

Add missing "size" and "path" words in the example, as the current example
is incorrect and will be rejected by the command.

The keywords were missing from very inception of devlink-resource man page

Fixes: 58b48c5d75e2 ("devlink: Update man pages and add resource man")
Signed-off-by: Przemek Kitszel <przemyslaw.kitszel@intel.com>
Reviewed-by: Michal Kubiak <michal.kubiak@intel.com>
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>