Commit 
dd8088d5a896 ("PM: runtime: Add pm_runtime_resume_and_get to
deal with usage counter") added a new runtime-PM API function without
updating the documentation in runtime_pm.rst.
Add the missing documentation.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Fixes: dd8088d5a896 ("PM: runtime: Add pm_runtime_resume_and_get to deal with usage counter")
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
       checked additionally, and -EACCES means that 'power.disable_depth' is
       different from 0
 
+  `int pm_runtime_resume_and_get(struct device *dev);`
+    - run pm_runtime_resume(dev) and if successful, increment the device's
+      usage counter; return the result of pm_runtime_resume
+
   `int pm_request_idle(struct device *dev);`
     - submit a request to execute the subsystem-level idle callback for the
       device (the request is represented by a work item in pm_wq); returns 0 on