I have written a tool including that functionality some time ago. Although I didn't find the time to polish it up before going public, it basically does what it is supposed to.
Expanding unit scope names is only part of the whole process, which consists of
resolve all unit aliases
expand unit scope names
group units
compress uses clause
Taking your example above it will convert
uses
sysutils, stdctrls;
into
uses
System.SysUtils,
Vcl.StdCtrls;
Feel free to adjust the sources to your needs.
UsesCleanerSource.zip