Follow up to r22457: cleanup and add extra comment.
Follow up to r22457: cleanup and add extra comment.

Suggested by: dlr

* subversion/libsvn_subr/path.c
  (svn_path_is_root): add comment explaining the need for this custom 
   implementation. Fix some whitespaces to match our coding guidelines.

git-svn-id: f8a4e5e023278da1e04e203c7fe051e3c4285d88@862566 13f79535-47bb-0310-9956-ffa450edef68

wbond/subversion,wbond/subversion,wbond/subversion,YueLinHo/Subversion,wbond/subversion,YueLinHo/Subversion,YueLinHo/Subversion,wbond/subversion,YueLinHo/Subversion,YueLinHo/Subversion,wbond/subversion,wbond/subversion,YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion