We use both -long-option and --long-option in tests. Switch to --long-option for consistency.
In the "llvm-readelf" mode, -long-option is discouraged as it conflicts with grouped short options and it is not accepted by GNU readelf.
While updating the tests, change llvm-readobj -s to llvm-readobj -S to reduce confusion ("s" is --section-headers in llvm-readobj but --symbols in llvm-readelf).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@359649 91177308-0d34-0410-b5e6-96231b3b80d8
Fangrui Song