Proper checks for vendor and ODM SKUs

If DEVICE_MANIFEST_FILE / ODM_MANIFEST_FILES is set, also include check
for empty vendor / odm SKU, respectively. Then, do cross product of
vendor SKUs and ODM skus, and check each possible combination.

Test: build with and without vendor skus
Test: m check-vintf-all
Bug: 148601741

Change-Id: I23cc81998e7afc36c43540bf6d615b4d4b288447