pathmap: Point QC HAL pathmaps directly to the source

Directly map to the actual HAL directory, including the
board platform. This lets project-path-for point directly
to the respective HALs.

Change-Id: Ic4ed61bbdea9d0b5683502bf84a8410e76858527
"LRX21U"
"LRX21V"
build: set qcom media variant to root path

Change-Id: If7d0dc3fc1789b14f5272be46c13a9146575ce79