Moved flight make code into flight/Makefile. This should speed up
rebuilds for GCS and keeps the top level Makefile tidier.
Change-Id: I9d33cb5c223b6a8ed2821435a5d63ecf4b97c6b8
This error of building any EF targets was found on Windows if used with
make V=1 verbose output option. The '--verbose' python script option was
used by the Windows make as a part of python script file name with
'file not found' error. Now it works. Still can't get the cause of that
error, though...
