build: fix project pathmap with legacy repos

 some devices still use (display/media)-legacy. Enable those
 trees to be handled via project pathmap.

Change-Id: I38b75ea49b3f7f5736eaaf9370bb72b2aaa42320

Conflicts:
	core/qcom_target.mk
qcom_target: Bring audio back to QSD8K.

Change-Id: I6e25b5f7e1652da34ec0e3e7f0e3e2688940d801