Revert "llvm-strings: support printing the filename"

Revert "llvm-strings: support printing the filename"

Also,

Revert "test: remove the archive before modifying it"
Revert "test: explicitly use gnu format"

This reverts commits r286778, r286729 and r286767, as they are randomly failing
on many bots (AArch64, x86_64).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@286820 91177308-0d34-0410-b5e6-96231b3b80d8