Fix comment NOTE about SetVLOGLevel

[hari90]

Fix the comment about SetVLOGLevel according to https://github.com/google/glog/pull/650 which added support for updating vmodule levels after vmodule level has been cached.

Fixes https://github.com/google/glog/issues/858

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 64.08%. Comparing base (45f99f5) to head (7e258ca).

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #1109      +/-   ##
==========================================
+ Coverage   63.57%   64.08%   +0.50%     
==========================================
  Files          20       20              
  Lines        2578     2578              
  Branches      894      906      +12     
==========================================
+ Hits         1639     1652      +13     
+ Misses        671      662       -9     
+ Partials      268      264       -4     

see 2 files with indirect coverage changes

[hari90]

Thanks for the PR.

Doesn't it make more sense to supply the updated information in the user guide, for instance, by updating this section?

I have put a basic description of SetVLOGLevel in the doc and more detailed information in the .h file. Let me know if this looks good enough.