Always collect lsdump paths from lsdump_paths.txt

This commit removes the code path that searches lsdump files by
traversing the directory.  Instead, always read the lsdump paths from
lsdump_paths.txt so that `create_reference_dumps.py` won't copy stale
lsdump files.

Bug: 121986692
Test: create_reference_dumps.py --llndk -lib libvulkan
Change-Id: I8c81dc1fd51d146da19a894c32e0df35907ba604
2 files changed