This commit fixes an issue with the parallel building problem.
Note: When calling $(MAKE) from a function call or from inside
another variable, instead of calling directly in target,
make cannot identify the make calls to distribute the process
load across processes. This makes the parallel building to
ommit the $(MAKE) calls in these situations from the parallelism.
Change-Id: I42ed5127a99a1a461c47edb4b4f8511e4b6e7e8d
Signed-off-by: Juan Manuel Cruz <juan.m.cruz.alcaraz@linux.intel.com>