Revert "Ensure imported targets in sibling dirs are deduplicated"

Revert commit 502610733f (Ensure imported targets in sibling dirs are
deduplicated, 2024-09-15, v3.31.0-rc1~92^2).  Also revert the change
from a copy of the logic made by commit cd418d4bb6 (Static libraries
de-duplication: keep first occurrence, 2024-09-29, v3.31.0-rc1~30^2).
The logic was de-duplicating based on the target name rather than based
on the library file path.

Fixes: #26371
Issue: #26284