fix build bring up to speed with google lunch
Load only the current product config makefile.
To reduce the start time.
With the change and previous change of doing clean step in only given paths,
start time of mm/mmm is reduced from ~5s to about 1s;
lunch time is reduced from ~40s to 3.5s.
add back vendor module check but remove restricted code (credit cm)
add code for p.e to use new product config file with faster lunch time