qcom_utils: allow overriding get-vendor-board-platforms

* Some devices need this function to return something, yet also do not
  set BOARD_USES_QCOM_HARDWARE. Allow them to override this.

Change-Id: I3cf78da39b006ba805ae35fde7379357faa10250
(cherry picked from commit 012cc275e09346ef7909b6a5a144aed59b375ccd)
1 file changed