[objcopy][NFC] Rename files to avoid clashing of archive members.

libtool uses file names to name members of an static library.
Files, located in different directories and having matching name,
would have the same name inside an archive. This is not a problem
for ld, but may be a problem for ar. This patch renames files
from ObjCopy library to avoid names clashing.

See https://reviews.llvm.org/D88827#3335814

Differential Revision: https://reviews.llvm.org/D120345